Appendix A - Cell Phone Nonresponse Bia Analysis

Appendix A_Nonresponse_Bias_Analysis_TPOPS.doc

Telephone Point of Purchase Survey

Appendix A - Cell Phone Nonresponse Bia Analysis

OMB: 1220-0044

Document [doc]
Download: doc | pdf

APPENDIX A







Nonresponse Bias in the Telephone Point of Purchase Survey:

A summary of three studies

Patrick Falwell and Madeleine Saxton

August 4, 2009


All views expressed on this poster are those of the authors and do not necessarily reflect the views or policies of the U.S. Bureau of Labor Statistics.

I. Introduction

The Telephone Point of Purchase Survey (TPOPS) is a random digit dialed (RDD) computer-assisted-telephone-interview (CATI) survey that collects outlet and expenditure information from households. It serves as the main source for the outlet sampling frame for the U.S. Commodities and Services (C&S) Pricing Survey for the Consumer Price Index (CPI). It is a rotating panel survey with each consumer unit participating for four consecutive quarters.1 The TPOPS is conducted by the Census Bureau for the Bureau of Labor Statistics (BLS). Since TPOPS’ inception in the second quarter of 1997, the response rate has fallen from 68.2% to 47.1% in the last quarter of 2008.2 Because of the decreasing response rate and because it is an Office of Management and Budget (OMB) requirement for clearance to conduct surveys, the BLS has embarked upon a non-response bias analysis of the TPOPS data.

One facet of the design of the TPOPS is that cell phone contacts are considered out-of-scope. The sample is drawn from banks of landline-only phone numbers. With the increase of cell-phone-only households, the BLS is assessing the potential bias associated with excluding cell-phone-only households and will take remedial action if a bias does indeed exist.

Cell-phone-only households have been the subject of several studies in the last several years. In 2004, the Current Population Survey (CPS) included questions in its supplement regarding the telephone service of households to measure how many were cell-phone-only. At that time, 6% of the households in the US used only cell-phones.3 In 2009, the National Health Statistics Reports revealed that in 2007, this number had almost tripled to 17.5%. Some states (Oklahoma and Utah) had rates over 25% of cell-phone-only households.4

This paper summarizes three studies that BLS conducted to assess if the TPOPS exhibits non-response bias.

The first study compares the demographics reported in TPOPS against the Census Bureau’s American Community Service (ACS). The ACS is a mandatory survey with a response rate of 97%. There are significant differences in the demographics between the two surveys.

The second study compares TPOPS complete responders with attritors and intermittent respondents as proxies for non-respondents. This analysis shows significant demographic and expenditure differences between age-race cohorts in the TPOPS population.

In the final study, the expenditures reported in the Consumer Expenditure (CE) Interview are reviewed to see if there is a difference between cell-phone-only households and those households that would be considered in-scope for TPOPS: cell-phone and landline households and landline only households. The category in which each household falls depends on what type of phone bills they indicated they had in the reference period.

These studies suggest that data in the TPOPS are not missing completely at random (MCAR). There are age-race cohorts that are under-represented in the TPOPS population, whereas others are over-represented. To correct for these issues, the BLS is exploring different ways of collecting and representing the data.

In the short-term, the recommendation of adjusting weights to correct for the under-representation of some cohorts is worth pursuing. In the long-term, the CPI will need to evaluate alternatives to the current land-line only RDD survey to provide its C&S Pricing sample frame.

1. TPOPS Response Rates



TPOPS response rates show a decreasing trend since BLS switched to an RDD/CATI survey in 1997. The tables below show the response rate from the 1st quarter in 2005 to the 4th quarter in 2008. The tables show the response rate steadily decreasing. Response rates are calculated according to OMB’s response rate definition


Unweighted Response Rate


Unweighted Response Rate = C a

C + R + NC + O + e(U)

C = number of completed interviews or sufficient partially completed interviews

R = number of refusals

NC = number of noncontacted sample units known to be eligible

O = number of eligible sample units not responding for reasons other than refusal

U = number of sample units of unknown eligibility, not completed

e = estimated proportion of sample units of unknown eligibility that are eligible,

(set to 0.27)


Response Rate by Quarter5


Quarter

Interviews

Non Contacts

Refusals

Estimate of Unknown Population

Total

Response Rate

Q971

3453

429

1008

174.96

5,065.0

68.2%

Q972

6330

940

1736

357.21

9,363.2

67.6%

Q973

9217

978

2994

522.18

13,711.2

67.2%

Q974

12086

1266

3800

741.15

17,893.2

67.6%

Q981

11946

2026

3354

769.23

18,095.2

66.0%

Q982

12000

2419

3363

747.63

18,529.6

64.8%

Q983

11969

2690

3340

740.34

18,739.3

63.9%

Q984

11996

2312

3601

910.71

18,819.7

63.7%

Q991

11752

1496

3909

984.15

18,141.2

64.8%

Q992

11514

1284

4034

793.26

17,625.3

65.3%

Q993

10884

1907

3668

736.29

17,195.3

63.3%

Q994

11,502

1,667

4,019

738.18

17,926.2

64.2%

Q001

17,205

3,081

6,736

1,367.8

28,389.8

60.6%

Q002

16,666

4,004

6,455

1,302.5

28,427.5

58.6%

Q003

18,041

3,481

6,378

1,292.8

29,192.8

61.8%

Q004

17,904

2,320

6,094

1,299.5

27,617.5

64.8%

Q011

17,821

2,819

5,671

1,345.1

27,656.1

64.4%

Q012

13,680

2,357

4,731

963.4

21,731.4

63.0%

Q013

13,641

2,411

4,503

944.5

21,499.5

63.5%

Q014

13,824

2,290

4,424

935.6

21,473.6

64.4%

Q021

13,240

1,934

4,753

891.5

20,818.5

63.6%

Q022

13,166

2,559

5,144

996.6

21,865.6

60.2%

Q023

13,602

2,001

5,087

984.2

21,674.2

62.8%

Q024

13,684

2,178

5,136

955.0

21,953.0

62.3%

Q031

14,210

2,233

5,431

1,033.3

22,907.3

62.0%

Q032

14,084

2,920

5,019

1,015.7

23,038.7

61.1%

Q033

13,705

2,352

5,402

1,020.6

22,479.6

61.0%

Q034

13,759

2,132

5,618

1,076.0

22,585.0

60.9%

Q041

13,303

2,611

5,714

1,055.7

22,683.7

58.7%

Q042

11,297

5,042

5,363

1,557.9

23,259.9

48.6%

Q043

12,643

4,364

4,664

1,534.7

23,205.7

54.5%

Q044

13,999

4,160

5,097

1,200.2

24,456.2

57.2%

Q051

14,245

4,562

5,223

1,271.4

25,301.4

56.3%

Q052

15,021

4,822

5,934

1,274.7

27,051.7

55.5%

Q053

14,961

4,796

5,808

1,225.8

26,790.8

55.8%

Q054

14,851

5,978

6,732

1,254.2

28,815.2

51.5%

Q061

15,009

6,983

7,825

1,338.4

31,155.4

48.2%

Q062

15,121

6,649

7,414

1,498.2

30,682.2

49.3%

Q063

14,939

7,532

5,857

1,488.8

29,816.8

50.1%

Q064

15,197

5,391

7,391

1,237.7

29,216.7

52.0%

Q071

13,276

7,130

6,553

1,365.1

28,324.1

46.9%

Q072

13,869

8,006

7,102

1,576.0

30,553.0

45.4%

Q073

13,538

7,332

7,032

1,385.9

29,287.9

46.2%

Q073

13,264

6,881

6,457

1,216.4

27,818.4

47.7%

Q081

13,207

6,506

5,898

1,101.3

26,712.3

49.4%

Q082

9,996

7,315

4,742

1,252.0

23,305.0

42.9%

Q083

11,507

5,992

5,458

1,124.6

24,081.6

47.8%

Q084

12,687

6,125

6,877

1,276.8

26,965.8

47.1%


Breakdown of Response Rate


Quarter

% Interviews

%Non Contacts

% Refusals

% Estimate of Unknown Population

 

Non-Cont./Ints.

Refs./Ints.

Q051

56.3%

18.0%

20.6%

5.0%

 

32.0%

36.7%

Q052

55.5%

17.8%

21.9%

4.7%

 

32.1%

39.5%

Q053

55.8%

17.9%

21.7%

4.6%

 

32.1%

38.8%

Q054

51.5%

20.8%

23.4%

4.3%

 

40.3%

45.3%

Q061

48.2%

22.4%

25.1%

4.3%

 

46.5%

52.1%

Q062

49.3%

21.7%

24.2%

4.9%

 

44.0%

49.0%

Q063

50.1%

25.3%

19.6%

5.0%

 

50.4%

39.2%

Q064

52.0%

18.5%

25.3%

4.2%

 

35.5%

48.6%

Q071

46.9%

25.2%

23.1%

4.8%

 

53.7%

49.4%

Q072

45.4%

26.2%

23.2%

5.2%

 

57.7%

51.2%

Q073

46.2%

25.0%

24.0%

4.7%

 

54.2%

52.0%

Q073

47.7%

24.7%

23.2%

4.4%

 

51.9%

48.7%

Q081

49.4%

24.4%

22.1%

4.1%

 

49.3%

44.7%

Q082

42.9%

31.4%

20.4%

5.4%

 

73.2%

47.4%

Q083

47.8%

24.9%

22.7%

4.7%

 

52.1%

47.4%

Q084

47.1%

22.7%

25.5%

4.7%

 

48.3%

54.2%


  • The two response rates by quarter tables suggest that TPOPS has experienced an abrupt decline in response rate. The average annual response rate from 2005 to 2008 was 54.8%, 49.9%, 46.5%, and 46.8%, respectively.

  • The cause of this decline can be attributed to a higher number of non-contacts and refusals. The combined average annual response rate of non-contacts and refusals from 2005 to 2008 was 40.5%, 45.5%, 48.7%, and 48.5%, respectively.



Response Rate by PSU


Area

Y2005

Y2006

Y2007

Y2008

East

Boston

52.7%

47.3%

45.3%

45.5%

Philadelphia

50.2%

44.0%

47.3%

48.5%

Pittsburgh

60.6%

56.8%

52.4%

52.5%

New York

39.3%

34.1%

29.5%

30.0%

NY-CT Suburbs

46.9%

44.1%

43.4%

42.8%

NJ Suburbs

49.9%

44.3%

42.0%

43.7%

X-Sized East

59.2%

44.9%

58.7%

55.8%

Midwest

Chicago

51.5%

48.2%

45.4%

45.5%

Detroit

57.9%

55.3%

50.3%

50.4%

St. Louis

65.1%

56.5%

56.0%

56.2%

Cleveland

61.4%

56.7%

51.3%

54.3%

Minneapolis

61.7%

59.9%

58.1%

58.9%

Milwaukee

60.1%

59.0%

54.5%

58.0%

Cincinnati

60.8%

55.5%

58.1%

57.0%

Kansas City

61.6%

60.2%

58.2%

61.3%

X-Sized Midwest

63.8%

49.8%

58.5%

58.4%

Y-Sized Midwest

68.6%

61.7%

64.1%

61.7%

South

Washington

56.9%

51.3%

47.5%

49.0%

Baltimore

57.2%

55.3%

48.5%

48.1%

Dallas

55.3%

49.6%

44.1%

45.9%

Houston

50.2%

45.4%

42.9%

41.6%

Atlanta

44.7%

40.8%

40.2%

41.1%

Miami

37.7%

33.7%

29.9%

30.4%

Tampa

49.8%

45.9%

45.0%

46.7%

X-Sized South

55.5%

50.7%

47.5%

47.0%

Y-Sized South

59.2%

55.7%

50.2%

52.1%

West

Los Angeles

44.6%

38.0%

35.8%

37.5%

LA Suburbs

53.3%

44.4%

40.0%

41.4%

San Francisco

50.6%

45.6%

42.9%

41.3%

Seattle

57.4%

53.2%

51.2%

50.3%

San Diego

52.8%

45.0%

41.7%

43.1%

Portland

62.6%

57.4%

56.1%

55.9%

Honolulu

46.3%

41.7%

41.7%

40.4%

Anchorage

61.4%

52.8%

51.4%

46.2%

Phoenix

55.1%

54.3%

48.4%

46.0%

Denver

59.0%

51.7%

52.2%

50.9%

X-Sized West

61.0%

48.7%

48.1%

51.4%

Y-Sized West

62.7%

62.2%

60.6%

58.2%





Response Rate by Region 2005-2008


Region/Panel

Interviews

Non Contacts

Refusals

Estimate of Unknown Population

Total Cases

Response Rate

East - Panel 1

13,370

9,254

6,735

2,187.8

31,546.81

42.4%

East - Panel 2

11,818

6,885

4,992

902.9

24,597.88

48.0%

East - Panel 3

10,720

3,840

4,453

797.9

19,810.58

54.1%

East - Panel 4

9,322

3,205

3,675

700.9

16,902.92

55.2%

 

 

 

 

 

 

 

Midwest - Panel 1

14,830

7,029

4,535

1,527.4

27,921.39

53.1%

Midwest - Panel 2

12,796

5,125

3,170

582.1

21,673.12

59.0%

Midwest - Panel 3

11,114

2,810

2,684

494.9

17,102.91

65.0%

Midwest - Panel 4

9,379

2,205

2,162

433.9

14,179.89

66.1%

 

 

 

 

 

 

 

South - Panel 1

19,556

12,048

9,935

2,620.9

44,159.89

44.3%

South - Panel 2

16,735

8,698

7,111

1,008.2

33,552.18

49.9%

South - Panel 3

14,550

4,929

5,905

872.4

26,256.37

55.4%

South - Panel 4

12,298

3,937

4,726

714.2

21,675.15

56.7%

 

 

 

 

 

 

 

West - Panel 1

15,482

9,910

7,415

2,298.2

35,105.24

44.1%

West - Panel 2

13,620

7,433

5,575

923.7

27,551.67

49.4%

West - Panel 3

12,171

4,320

4,902

802.2

22,195.17

54.9%

West - Panel 4

10,632

3,688

4,111

700.9

19,131.92

55.6%


Response Rate by PSU Size/Panel


PSU - Size Panel

Interviews

Non Contacts

Refusals

*Estimate of Unknown Population

Total Cases

Response Rate

A - Panel 1

35,186

23,186

18,418

5,630.58

82,420.58

42.7%

A - Panel 2

31,363

17,484

13,831

2,287.17

64,965.17

48.3%

A - Panel 3

28,312

10,129

12,281

2,019.60

52,741.60

53.7%

A - Panel 4

24,864

8,554

10,230

1,776.60

45,424.60

54.7%

 

 

 

 

 

 

 

X - Panel 1

6,780

3,599

2,811

803.52

13,993.52

48.5%

X - Panel 2

5,820

2,937

2,021

292.41

11,070.41

52.6%

X - Panel 3

5,081

1,559

1,633

247.05

8,520.05

59.6%

X - Panel 4

4,255

1,294

1,283

208.98

7,040.98

60.4%

 

 

 

 

 

 

 

Y - Panel 1

3,689

2,124

1,479

426.06

7,718.06

47.8%

Y - Panel 2

3,465

1,860

1,179

184.68

6,688.68

51.8%

Y - Panel 3

3,293

1,070

1,063

170.91

5,596.91

58.8%

Y - Panel 4

3,025

986

952

157.14

5,120.14

59.1%




  • The response rate of the Midwest was clearly higher than the response rates of the other three regions for all four panels of interviews.

  • The Midwest’s A-sized (self-representing) PSUs also had higher response rates than other regions’ PSUs and have not experienced the abrupt declines in response rate as have other PSUs. The Midwest’s A-sized PSUs had an average response rate of 55.2%, while the East, the South, and the West had average response rates of 43.8%, 43.2%, and 45.3%, respectively. The average decline in response rate from 2005 to 2008 for the Midwest was 4.8%, while East, the South, and the West had average declines of 6.1%, 7.0%, and 9.0%.

  • New York City (A109) had the lowest response rate in 2008, and was continually among the lowest responding PSUs from 2005 to 2008.

  • The X-sized PSUs (metropolitan non-self-representing) and the Y-sized PSUs (nonmetropolitan non-self-representing) (53.2% and 57.4% respectively) had higher average response rates than A-sized PSUs.


  1. Comparison of TPOPS Demographic Data to American Community Survey Data


A comparison of TPOPS socio-demographic data to the Census Bureau’s American Community Survey’s (ACS) socio-demographic data is necessary to analyze potential non-response bias in TPOPS.

TPOPS only collects demographic data from the respondent and not the other members of the consumer unit. This analysis assumes that the demographics of the TPOPS respondent represent the demographics of the entire consumer unit. The demographics of the consumer units are then compared against the demographic data of ACS householders. ACS reports the percentages of total householders that fall into various demographic groups, and these percentages are assumed to be the urban population’s demographic percentages. These percentages are used to calculate the expected number of TPOPS consumer units, against which the observed number of TPOPS consumer units could be compared using Chi-Square tests.

Additional adjustments are made for respondents who did not answer demographic questions. The rate of non-response for race questions averages 16.6% between 2005 and 2008, and the rate of non-response for age questions averaged 14.6% between 2005 and 2008. The weight of non-response consumer units was reallocated, however, using the frequency distribution of those responding to race and age questions for each quarter and each population sampling unit (PSU). For example, if the weight of non-response equals 100 for a given PSU, and the distribution of those responding to race questions was 30% white, 30% black, 30% Hispanic, and 10% Asian, then the reallocated weight equals 30, 30, 30, and 10 for each group, respectively. After the weight of non-responders is reallocated, the quarterly distributions of each race and age group were averaged by year.


2005


2005

RACE OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

American Indian and Alaska Native

0.6%

558,600

0.6%

587,531

1,498

Asian

4.5%

4,189,497

2.9%

2,732,643

506,606

Black or African American

13.6%

12,661,592

8.7%

8,100,797

1,642,830

Native Hawaiian and Other Pacific Islander

0.1%

93,100

0.3%

267,325

326,039

Two or more races

1.3%

1,210,299

1.7%

1,559,231

100,598

Some other race

5.1%

4,748,097

5.1%

4,758,278

22

White

74.8%

69,638,754

80.7%

75,094,133

427,365

Total

 

93,099,938

 

93,099,938

3,004,959

 

 

 

 

 

 

ORIGIN OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

Hispanic or Latino origin

12.5%

11,637,492

10.%

9,246,733

491,148

Other alone, not Hispanic or Latino

19.6%

18,247,588

14.9%

13,863,749

1,053,183

White alone, not Hispanic or Latino

67.9%

63,214,858

75.1%

69,696,719

664,630

Total

 

93,099,938

 

92,807,201

2,208,961



2006


2006

RACE OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

American Indian and Alaska Native

0.6%

637,721

0.7%

770,658

27,711

Asian

4.5%

4,782,910

1.7%

1,760,818

1,909,515

Black or African American

13.5%

14,348,729

16.7%

17,736,493

799,858

Native Hawaiian and Other Pacific Islander

0.1%

106,287

0.2%

247,575

187,817

Two or more races

1.4%

1,488,016

2.0%

2,169,588

312,187

Some other race

5.5%

5,845,778

3.9%

4,121,087

508,839

White

74.5%

79,183,726

74. 8%

79,480,660

1,113

Total

 

106,286,880

 

 

106,286,880

 

 

 

 

 

 

ORIGIN OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

Hispanic or Latino origin

12.8%

13,604,721

7.1%

7,536,609

2,706,559

Other alone, not Hispanic or Latino

19.6%

20,832,229

21.7%

23,069,314

240,231

White alone, not Hispanic or Latino

67.6%

71,849,931

71.2%

75,748,026

211,485

Total

 

106,286,880

 

106,353,949

3,158,275


2007


2007

RACE OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

American Indian and Alaska Native

0.6%

576,854

0.8%

749,250

51,521

Asian

4.5%

4,326,408

2.3%

2,247,170

999,266

Black or African American

13.6%

13,075,366

7.4%

7,090,064

2,739,796

Native Hawaiian and Other Pacific Islander

0.1%

96,142

0.3%

272,899

324,964

Two or more races

1.4%

1,345,994

1.6%

1,573,829

38,566

Some other race

5.4%

5,191,690

4.5%

4,357,384

134,073

White

74.4%

71,529,945

83.1%

79,851,803

968,173

Total

 

96,142,399

 

96,142,399

5,256,358

 

 

 

 

 

 

ORIGIN OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

Hispanic or Latino origin

13.0%

12,498,512

8.8%

8,461,975

1,303,645

Other alone, not Hispanic or Latino

19.7%

18,940,053

12.4%

11,784,461

2,703,397

White alone, not Hispanic or Latino

67.3%

64,703,834

78.8%

75,120,052

1,676,834

Total

 

192,284,797

 

192,284,797

5,683,877




Age Comparison


2005


2005

AGE OF HOUSEHOLDER

ACS Percentage 

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

Under 35 years

23.4%

21,712,993

16.4%

15,224,323

1,939,062

35 to 44 years

20.8%

19,300,438

19.9%

18,502,283

33,007

45 to 54 years

20.8%

19,300,438

22.9%

21,252,650

197,463

55 to 64 years

15.2%

14,104,166

18.4%

17,086,568

630,645

65 to 74 years

9.7%

9,000,685

12.7%

11,819,010

882,484

75 to 84 years

7.7%

7,144,874

7.7%

7,150,091

4

85 years and over

2.5%

2,319,764

1.9%

1,755,644

137,183

Total

 

92,790,568

 

92,790,568

3,819,847


2006


2006

AGE OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

Under 35 years

22.1%

29,292,845

13.1%

17,335,664

4,880,856

35 to 44 years

20.8%

27,569,736

18.3%

24,236,423

403,013

45 to 54 years

21.2%

28,099,923

22.6%

30,003,476

128,951

55 to 64 years

15.9%

21,074,942

20.6%

27,264,141

1,817,617

65 to 74 years

9.8%

12,989,587

13.9%

18,433,391

2,281,443

75 to 84 years

7.6%

10,073,557

9.8%

12,931,239

810,671

85 years and over

2.7%

3,578,764

1.8%

2,342,474

427,079

Total

 

132,546,808

 

132,546,808

10,749,631


2007


2007

AGE OF HOUSEHOLDER

ACS Percentage

Expected Number of Consumer Units

TPOPS Percentage

Observed Number of Consumer Units

X^2

Under 35 years

21.8%

16,528,804

11.2%

8,463,854

3,935,155

35 to 44 years

20.4%

15,467,321

17.2%

13,072,395

370,825

45 to 54 years

21.3%

16,149,703

21.9%

16,607,394

12,971

55 to 64 years

16.3%

12,358,693

22.0%

16,686,084

1,515,234

65 to 74 years

9.9%

7,506,200

15.2%

11,535,562

2,162,980

75 to 84 years

7.5%

5,686,515

10.1%

7,670,160

691,961

85 years and over

2.7%

2,047,145

2.4%

1,784,752

33,632

Total

 

75,820,202

 

75,820,202

8,722,760




The differences between the TPOPS and ACS samples are statistically significant for race and age, for all years between 2005 and 2007. The differences in age of ACS householder percentages and TPOPS respondent percentages are particularly of interest in terms of TPOPS failing to collect enough from certain cohorts. The older age strata for TPOPS respondents represent a much larger percentage than the younger age strata when compared to ACS householders for all three years. From 2005 to 2007, the combined percentage of the two youngest strata fell from 36.4% to 28.4%. As with the TPOPS response rates for individual PSUs, the response rates may vary considerably among individual cohorts


In comparison to the age demographics, the TPOPS race demographics, while statistically significant, do not seem to be as problematic. The individual race cohorts fluctuate considerably between years, with some cohorts being closer to the ACS percentages in one year, then being considerably different in the next. The white cohort was always overrepresented, however, whereas other cohorts were underrepresented by as much as 6% to 7%. The black cohort was underrepresented by around 6% in 2005 and 2007, but was actually overrepresented by 3% in 2006. The Hispanic cohort was underrepresented by 3%, 5%, and 6% in the three years, respectively. The Asian cohort was underrepresented by between 2% to 3%. Other cohorts composing around 5% of TPOPS respondents were more in line with the percentages reported by ACS householders.

3. Comparison of Respondents Completing Four TPOPS Interviews and Dropout Respondents


In an attempt to analyze the characteristics of TPOPS non-responders, the expenditure means per TPOPS Category, or POPSCAT, and demographic data were compared for TPOPS respondents who completed four quarters of interviews (complete respondents) and respondents who dropped out of the survey after completing one or two interviews (attritors). The TPOPS attritors served as proxies for non-responders under the assumption that non-participation in TPOPS after one or two interviews indicates similarity to those who refuse to participate or are non-contacts. The time period of 2005 to 2008 was again used in this analysis; however, only respondents who had a chance to complete four interviews within that time period were included. Therefore, a respondent who completed his or her fourth interview in the first quarter of 2005 or began the survey in the second quarter of 2008 was not considered. Overall, there were 21,256 consumer units that completed four quarters of interviews and 22,446 attritor consumer units that completed one or two interviews.


The expenditure means of each POPSCAT were calculated for both the complete responders and the attritors and tested for significant differences using two-sample t-tests. There is a statistically significant difference in expenditure means for 33% of the POPSCATs, and the breakdown of significance by major groups is listed in the table below. The differences in expenditure mean are statistically insignificant for the majority of every major group’s POPSCATs except for Apparel.

Major Group

Number of Stat. Insig. POPSCAT means

Number of Stat. Sig. POPSCAT means

Apparel

7

16

Education/Communication

12

5

Food

36

25

General Items

10

6

Household Items

28

11

Medical

9

0

Recreation

26

6

Transportation

16

3


The large percentage of statistically insignificant differences in POPSCAT expenditure means hopefully suggest that there are not large differences in overall expenditure behavior between complete responders and attritors.


The demographic data for the always participating consumer units and the dropout consumer units was also calculated. Unfortunately, the dropout consumer units did not respond to demographic questions a considerable percentage of the time (Race – 16.4%, Age – 17.6%, Gender – 15.4%). In order to make a side-by-side comparison of the demographics of the always-participating consumer units and the dropout consumer units, the weight of the non-responding consumer units had to be redistributed to the demographic categories. The four year population mean was calculated for each PSU and the rates of non-response were calculated for each PSU and quarter. The final weights of consumer units responding to demographic questions were then adjusted to account for non-response and to equal the four-year population mean of each PSU.



Race Comparison

Completed 4 Interviews Q051 - Q081

Dropouts Q051 - Q081

 

# Consumer Units

Percent

 

# Consumer Units

Percent

White

75,391,466

85.5%

White

67,874,172

75.2%

Black

5,982,369

6.8%

Black

10,360,444

11.5%

Other

3,048,919

3.5%

Other

5,967,660

6.6%

Asian

1,953,697

2.2%

Asian

3,084,017

3.4%

Multi-race

1,163,421

1.3%

Multi-race

1,820,466

2.0%

American Indian

441,106

0.5%

American Indian

735,191

0.8%

Hawaiian/Pacific Islander

163,071

0.2%

Hawaiian/Pacific Islander

438,379

0.5%


Completed 4 Interviews Q051 - Q081

Dropouts Q051 - Q081

 

# Consumer Units

Percent

 

# Consumer Units

Percent

Hispanic or Latino Origin

6,117,696

6.9%

Hispanic or Latino Origin

11,136,107

12.3%

Other, No Latino Origin

10,365,866

11.8%

Other, No Latino Origin

17,208,459

19.1%

White, No Latino Origin

71,660,487

81.3%

White, No Latino Origin

61,935,763

68.6%



Age Comparison

Completed 4 Interviews Q051 - Q081

Dropouts Q051 - Q081

 

# Consumer Units

Percent

 

# Consumer Units

Percent

UNDER 35

7,156,167

8.1%

UNDER 35

21,140,559

23.4%

BW 35-44

13,088,502

14.9%

BW 35-44

21,176,892

23.5%

BW 45-54

20,013,373

22.7%

BW 45-54

19,680,519

21.8%

BW 55-64

20,152,813

22.9%

BW 55-64

14,605,002

16.2%

BW 65-74

15,021,715

17.0%

BW 65-74

7,805,394

8.6%

BW 75-84

10,303,167

11.7%

BW 75-84

4,467,518

5.0%

OVER 85

2,408,314

2.7%

OVER 85

1,446,224

1.6%


Gender Comparison


Completed 4 Interviews Q051 - Q081

Completed 4 Interviews Q051 - Q081

 

# Consumer Units

Percent

 

# Consumer Units

Percent

Male

32,379,932

36.7%

Male

33,797,690

37.4%

Female

55,764,117

63.3%

Female

56,524,418

62.6%


The method of redistributing the final weight of non-responders precluded formal significance testing to determine if survey participation is independent of demographic characteristics. It still appears that there are considerable differences between the samples. The percentage of whites is much higher among those who completed the survey all four quarters, while the percentage of blacks and Hispanics is lower. The age demographics of the two groups appear particularly distorted. The older age ranges make up a large percentage of those who completed all four interviews, while the younger age ranges compose a large percentage of the dropout consumer units. While the demographic differences cannot be definitively confirmed, they do suggest that the consumer units completing four quarters of TPOPS interviews and those dropping out of the survey are different.


4. Comparison of Mean POPSCAT Expenditures for Cell Phone-Only and Landline Telephone Consumer Units in the Consumer Expenditure Survey


A sample of likely cell phone-only households was established using data from the Consumer Expenditure (CE) Interview Survey. A consumer unit was identified as a cell phone-only household if no expenditure for local telephone service was reported in any quarter of data 2006-2007. Overall, 23,250 CPI-Urban consumer units participated in the CE Interview Survey from 2006-2007, and the breakdown of households per telephone status is listed in the table below.

Group

Number of Consumer Units

Percent of Total

Landline and Cell Phone

11,324

48.7%

Landline Only

7,495

32.2%

Cell Phone Only

3,067

13.2%

No Telephone Expense

1,364

5.9%


Each consumer unit’s expenditures were annualized and classified by TPOPS expenditure categories, or POPSCAT. The expenditure mean of each POPSCAT was calculated for each of the groups above, and the expenditure means were compared using a two-sample t-test. Overall, the most important analysis is the comparison between cell phone-only consumer units and the consumer units that would compose the TPOPS sample - consumer units with both landline and cell phone expenses and consumer units with landline expenses only.

It should be noted that certain POPSCATs, especially from the Food major group, were not included in the analysis because they are only reported in the Consumer Expenditure Survey’s Diary survey. The Diary survey asks a consumer unit to report its expenditures during a two week period every quarter. It is difficult to determine if a consumer unit is cell phone-only given that it may not have received a cellular telephone bill during that two week survey period. In contrast, the CE Interview Survey has a three month recall period that covers an entire quarter, meaning no expenditure will be excluded due to a time gap in a consumer unit’s participation in the survey.

Expenditure means were compared for 140 POPSCATs using the two-sample t-test.6 Using a level of significance, α = 0.025, 94 POPSCATs, or 67.1% of all POPSCATs, had statistically significant differences in mean expenditures. The breakdown of statistical significance by POPSCAT major group is as follows:


Major Group

Number of Stat. Insig. POPSCATS

Number of Statistically Sig. POPSCATS

Apparel

12

11

Education/Communication

4

9

Food

0

1

General Items

6

8

Household Items

9

28

Recreation

9

22

Transportation

8

12


In addition to the comparison of expenditure means, analysis of the demographics of the cell phone-only sample and the TPOPS-eligible sample also implies that there are considerable differences between the two groups. The difference in age demographics seems most striking, and Chi-square tests for independence also showed that differences in gender, race, and salary were statistically significant.


Age Span

Landline+Cell/Landline Only

Cell Phone-Only

UNDER 35

18.0%

61.2%

BW 35-44

21.2%

17.1%

BW 45-54

21.9%

12.5%

BW 55-64

17.3%

7.02%

BW 65-74

10.8%

1.8%

BW 75-84

8.1%

0.3%

OVER 85

2.7%

0.1%

The null hypothesis that cell phone status is independent of age was rejected by a Chi-square test of independence. (χ2 = 2740.53, df = 6, p-value = <.0001).


Gender

Landline+Cell/Landline Only

Cell Phone-Only

Male

44.9%

52.9%

Female

55.1%

47.1%

The null hypothesis that cell phone status is independent of gender was rejected by a Chi-square test of independence. (χ2 = 63.46, df = 1, p-value = <.0001).


Race

Landline+Cell/Landline Only

Cell Phone-Only

White

81.1%

79.8%

Black

12.4%

12.8%

Asian

4.5%

4.9%

Hawaiian/Pac. Islander

1.2%

1.4%

Amer. Indian

0.5%

0.7%

Multiple Race

0.4%

0.4%

The null hypothesis that cell phone status is independent of race was not rejected by a Chi-square test of independence. (χ2 = 5.344, df = 5, p-value = .3753).


 

Landline+Cell/Landline Only

Cell Phone-Only

Hispanic or Latino Origin

12.7%

18.0%

Other Only, No Hispanic Origin

18.4%

19.7%

White Only, No Hispanic Origin

68.9%

62.3%

The null hypothesis that cell phone status is independent of Hispanic origin was rejected by a Chi-square test of independence. (χ2 = 71.96, df = 2, p-value = <.0001).


Salary

Landline+Cell/Landline Only

Cell Phone-Only

<$10,000

21.3%

23.0%

$10,000 - $30,000

21.5%

29.2%

$30,000 - $50,000

17.1%

22.8%

$50,000 - $70,000

12.5%

11.0%

$70,000 - $90,000

9.1%

6.8%

$90,000 - $125,000

9.1%

4.5%

$125,000 - $200,000

8.1%

2.4%

>$250,000

1.4%

0.3%

The null hypothesis that cell phone status is independent of salary was rejected by a Chi-square test of independence. (χ2 = 333.65, df = 7, p-value = <.0001).


The statistically significant differences in overall expenditure and demographics suggest that the cell phone-only and TPOPS-eligible populations are not very similar. For TPOPS, however, the main concern is whether cell phone-only consumer units purchase goods and services at outlets, where price change behavior is different and the subsequent effect on the CPI is different. The CE Interview Survey does not collect data on outlets, and drawing conclusions from analysis of the expenditure means of individual POPSCATs or major groups is difficult.


A comparison of the major groups with the highest and lowest percentage of statistically significant POPSCAT expenditure means underlies the difficulty in drawing definite conclusions. The Housing major group had the largest percentage of POPSCATs with statistically significant expenditure means. The Housing major group includes a wide range of POPSCATs from lodging away from home to household appliances and services. After classifying the POPSCATs into several categories, it becomes more certain that there are general differences between the expenditure behaviors of the two samples. For instance, all of the POPSCATs for household services, household decorations, and furniture are statistically significant.



Significant

Insignificant

Household Services

Fuel Oil, Cooking Fuel, Water/Sewer Service, Garbage Collection, Home Repair, Housekeeping Services, Lawn/Garden Services, Major Appliance Repair, Reupholstery


Household Decorations

Floor Coverings, Window Coverings, Linens, Sofas, Mattresses, Lamps/Clocks


Furniture

Living Room Chairs/Tables, Kitchen/Dining Room Furniture, Infants’ Furniture, Outdoor Furniture, Bookcases/Desks


Major Appliances

Refrigerators/Freezers, Stoves/Ovens/Microwaves

Washers/Dryers

Small Appliances

Vacuums, Small Kitchen Appliances, Heating Equipment

Power Tools, Non-powered Tools

Miscellaneous

Lodging away from Home, Indoor Plants, Dishes, Lawn/Garden Equipment

Lawn/Garden Supplies/Insecticides, Moving/Freight Services, Paint, Kitchen Utensils/Cooking Ware








In contrast to the Housing major group, the Apparel major group had the lowest percentage of statistically insignificant differences in mean expenditure. It appears that, similar to the Housing major group, there is a general difference in expenditure behavior between the cell-phone-only and TPOPS-eligible populations.


Significant

Insignificant

Men’s Apparel

Men’s Shirts

Men’s Coats/Jackets, Men’s Sportswear, Men’s Footwear, Men’s Pants, Men’s Ties/Belts/Wallets, Men’s Underwear/Sleepwear, Men’s Suits

Women’s Apparel

Women’s Sportswear, Women’s Footwear, Women’s Tops/Skirts/Pants, Women’s Underwear/Nightwear, Women’s Outerwear

Women’s Hoisery, Women’s Dresses, Women’s Suits,

Children’s/Infants’ Apparel

Boy’s/Girl’s Footwear, Boy’s Clothing, Girl’s Clothing, Infants’ Clothing,

Infants’ Underwear/Diapers,

Miscellaneous

Watches

Jewelry


Overall, the characteristics of the cell-phone-only population are considerably different from the characteristics of the TPOPS-eligible population. In comparison to the TPOPS-eligible population, the cell phone-only population is more racially diverse, younger, less wealthy, and more likely to be male. The cell phone-only population’s expenditure behavior seems considerably different from the TPOPS-eligible population’s expenditure behavior, because 67% of the POPSCATs have statistically significant differences in expenditure means.

5. Summary and recommendations

The TPOPS is used as the main source for the outlets in the CPI’s C&S Pricing Survey. Because there is no comparable source against which to compare the CPI’s outlet frame, the demographics and expenditures of TPOPS respondents are used as proxies and compared against similar data from the American Community Survey and the Consumer Expenditure Quarterly Interview Survey.


In the first study, we compared the demographics of the TPOPS’ respondents to the demographics reported in the ACS. This comparison showed that the differences between the age cohorts in ACS and TPOPS are significantly different. TPOPS over-represents older cohorts and under-represents younger cohorts. The design of TPOPS excludes cell-phone numbers from its sample, which may explain this under-representation of the younger population. This study also shows that there are statistically significant differences in the race of TPOPS respondents compared to ACS households, although the differences were less pronounced than the age differences.


The next study compared expenditures and demographics of complete and dropout respondents from the TPOPS. Around 33% of the POPS categories that were surveyed are significantly different between these two groups of respondents. Because of high item non-response, the demographic comparisons are less conclusive.


The final study focuses solely on data from the Consumer Expenditure Quarterly Interview Survey. The differences in the POPSCAT expenditures means between cell-phone-only consumer units and land-line-only and land-line/cell-phone consumer units were statistically significant for 94 out of the 140 POPS categories compared. The differences between these two populations’ expenditures may indicate that the two populations obtain goods and services from different sources.


These studies show that expenditure and demographic data in the TPOPS are likely not missing completely at random (MCAR). There are age-race cohorts that are under-represented in the TPOPS population, whereas others are over-represented. Because expenditures and demographics are proxies for the outlets reported, it is unclear if the outlets reported in the TPOPS indicate a non-response bias. These studies do indicate a need for further analysis. To address the issues raised in this research, the BLS is exploring different ways of collecting and representing the data.

In the short-term, the recommendation of adjusting population weights to correct for the under-representation of some cohorts needs further research. In the long-term, the CPI will need to evaluate alternatives to the current design of the land-line only RDD TPOPS survey to provide its C&S Pricing sample frame.

Appendix A - Comparison of POPSCAT Expenditure Means of Respondents Completing Four TPOPS Interviews and Dropout Respondents7


POPSCAT

POPSCAT Title

T Statistic

Completed Consumer Unit Expenditure Reports

Completed Consumer Unit Expenditure Mean

Attritor Consumer Unit Expenditure Reports

Attritor Consumer Unit Mean Expenditure

T17

Ship Travel or Passenger Cruises

3.26

708

$5,599.94

172

$4,119.91

H22

Heating or Cooling Equipment or Home Safety Devices

2.43

866

$763.64

300

$543.68

H16

Occasional Furniture such as Bookcases, Desks, or Ottomans

2.13

701

$412.40

260

$325.12

H20

Vacuums or Other Electric Floor Cleaning Equipment

2.07

1,078

$231.11

397

$197.51

E17

Local or Long Distance Landline Telephone Service including Prepaid Phone Cards

2.03

369

$52.47

21

$41.76

H40

Inside Home Maintenance or Repair

1.99

1,791

$5,990.30

497

$4,548.37

H04

Other Household Fuels For Heating or Cooking such as Propane, Firewood, or Coal

1.96

905

$466.27

273

$376.80

H03

Fuel Oil

1.69

607

$1,581.04

234

$1,428.83

H26

Indoor Plants or Fresh Cut Flowers

1.58

2,006

$81.22

648

$70.27

E06

Day Care Providers including Nursery Schools

1.56

372

$4,236.65

185

$3,662.54

M01

Prescription Drugs

1.54

2,585

$76.43

643

$68.60

R09

Pets, Pet Supplies or Accessories

1.46

780

$55.18

276

$44.17

F34

Roasted, Instant, or Freeze Dried Coffee

1.39

1,812

$10.14

482

$9.33

H19

Stoves, Ovens or Microwave Ovens

1.39

686

$729.60

262

$454.93

H18

Washers or Dryers

1.36

527

$826.04

230

$760.93

F57

Wine for Home Use

1.34

2,149

$156.11

598

$131.17

F39

Butter or Margarine

1.24

1,648

$4.33

468

$4.09

R01

Televisions

1.05

1,073

$979.83

369

$908.12

F54

Catered Events or Board

0.98

151

$2,473.32

43

$1,781.58

T12

Motor Vehicle Repair

0.88

2,288

$1,433.51

666

$1,206.50

T05

Gasoline, Diesel, or Alternative Fuels

0.88

4,259

$94.47

1,479

$64.86

R30

Newspaper or Magazine Subscriptions

0.86

1,735

$159.49

468

$143.59

H15

Outdoor Furniture

0.82

791

$419.62

247

$382.30

R13

Unpowered Boats or Trailers

0.80

280

$4,931.54

68

$3,948.82

M08

Hospital Services

0.79

1,507

$2,655.78

544

$2,182.50

H05

Residential Water or Sewer Service

0.77

2,610

$685.46

842

$617.98

A05

Men's Active Sportswear such as Exercise Apparel or Bathing Suits

0.72

1,784

$380.47

679

$258.28

R10

Pet Services

0.70

1,007

$207.01

321

$194.88

G15

Checking Accounts, Credit Card Fees, or Other Bank Services

0.64

1,085

$107.79

399

$90.72

G01

Cigarettes

0.60

779

$43.20

335

$41.69

E13

Online or Other Information Services

0.59

2,453

$216.90

776

$204.78

R25

Club Membership Dues such as Recreational Clubs, Fraternal or Civic Organizations, or Fees Paid for Participant Sports

0.55

1,662

$707.56

440

$670.12

H38

Major Appliance Repair

0.49

1,170

$648.00

353

$567.12

R18

Cameras or Other Photographic Equipment excluding Film

0.33

1,888

$427.30

571

$419.18

R07

Prerecorded or Blank Audio Tapes, CDs or Records

0.32

923

$61.15

291

$59.26

F40

Salad Dressing or Mayonnaise

0.30

1,917

$5.42

558

$5.27

M05

Dental Services

0.29

2,902

$925.40

783

$906.11

H29

Non-powered Tools, or Miscellaneous Hardware

0.26

1,720

$194.80

520

$189.04

E15

Calculators, Typewriters, or Other Information Processing Equipment

0.25

565

$67.06

222

$65.08

T19

Taxi Fare

0.24

397

$99.57

143

$96.45

R27

Admissions to Sporting Events

0.22

1,164

$459.07

444

$445.34

M02

Internal or Respiratory Over-The-Counter Drugs

0.18

596

$20.78

196

$20.42

F52

Meals or Snacks at Schools or Employer Provided Cafeterias, Dining Rooms or Snacks Bars

0.17

938

$29.63

301

$29.29

F26

Lettuce

0.17

1,607

$3.87

458

$3.83

T03

Leased Cars, Trucks, or Vans

0.15

301

$19,983.00

90

$19,654.96

F06

Cakes or Cupcakes (excluding Frozen)

0.07

1,108

$19.92

430

$19.71

H17

Refrigerators or Home Freezers

0.06

573

$964.28

210

$958.14

E07

Tuition or Fixed Fees for Technical or Vocational Schools

0.05

347

$10,665.92

137

$10,531.58

H39

Reupholstery of Household Furniture

0.04

301

$1,273.60

72

$1,255.25

G10

Funeral Services

0.00

732

$5,618.07

180

$5,618.08

T20

Car or Van Pools

-0.10

44

$175.91

25

$184.64

H23

Household Decorative Items Including Clocks or Lamps

-0.10

1,531

$300.02

594

$303.22

F56

Distilled Spirits for Home Use

-0.12

1,269

$130.34

385

$131.53

F10

Uncooked Beef or Veal including Frozen

-0.13

2,610

$31.09

790

$31.34

F42

Soups

-0.13

2,079

$10.06

696

$10.12

T01

New Cars, Trucks, or Vans

-0.15

2,152

$31,630.68

596

$31,800.46

R11

Veterinarian Services

-0.20

1,701

$399.48

503

$409.13

R14

Bicycles or Bicycling Accessories

-0.20

1,155

$321.40

410

$327.97

M09

Adult Day Care

-0.22

16

$3,331.88

14

$3,652.64

M04

Physician's Services

-0.31

3,175

$1,024.32

926

$1,086.18

G02

Tobacco Products Other Than Cigarettes

-0.34

197

$44.79

75

$47.56

F18

Cheese or Cheese Products

-0.34

2,204

$7.66

612

$7.78

R31

Books Purchased Through Book Clubs

-0.37

503

$159.01

173

$168.46

T14

Local Vehicle Registration

-0.38

886

$169.76

336

$175.08

F47

Baby Food

-0.40

190

$32.81

85

$34.95

F50

Full Service Meals or Snacks

-0.42

2,462

$81.74

698

$83.65

A22

Watches

-0.43

1,426

$206.62

538

$226.02

A23

Jewelry

-0.49

1,319

$640.08

426

$725.69

F37

Candy or Chewing Gum

-0.50

1,462

$8.96

476

$9.33

R04

Blank or Pre-recorded Video Cassettes and Video Discs

-0.52

859

$57.59

277

$60.32

G16

Tax Return Preparation or Other Accounting Services

-0.53

2,174

$356.16

700

$416.58

R29

Single Copy Newspapers or Magazines

-0.55

1,408

$7.93

548

$8.25

R26

Admissions such as Movies, Concerts, or Theme Parks

-0.58

1,900

$95.00

679

$100.00

F28

Other Fresh Vegetables including Fresh Herbs

-0.62

1,638

$15.63

446

$16.70

H13

Kitchen or Dining Room Furniture

-0.65

1,020

$1,317.52

372

$1,435.41

H10

Bedroom Furniture Including Mattresses and Springs

-0.66

1,212

$1,304.79

480

$1,361.80

H36

Gardening or Lawn Care Services

-0.67

1,486

$1,583.30

393

$1,712.14

G14

Watch or Jewelry Repair

-0.67

1,233

$79.94

357

$88.85

R23

Sewing Machines, Fabric or Sewing Supplies

-0.69

1,300

$208.21

375

$226.56

H35

Housekeeping Services

-0.72

751

$2,408.42

190

$2,639.67

F08

Crackers or Other Bread Products

-0.73

1,780

$5.86

551

$6.12

F48

Prepared Salads or Salad Bars, excluding Restaurants

-0.73

937

$9.36

272

$9.85

T04

Car, Truck, or Van Rental

-0.73

1,305

$757.51

299

$816.58

R24

Musical Instruments or Musical Accessories

-0.73

1,006

$1,018.13

307

$1,167.60

F44

Chips, Nuts, or Other Snacks excluding Candy

-0.75

1,698

$14.29

571

$14.88

F15

Processed Fish or Seafood, including Frozen, Canned or Cooked

-0.77

1,799

$15.04

488

$15.85

A12

Women's Suits or Suit Components

-0.78

664

$356.96

244

$390.76

E05

Tuition or Fixed Fees for Private Elementary or High Schools

-0.81

348

$4,598.74

139

$5,432.47

T02

New Motorcycles

-0.82

145

$11,626.83

52

$13,336.54

E04

Tuition or Fixed Fees for a College or University

-0.83

818

$9,761.43

237

$10,955.24

F16

Eggs or Egg Substitutes

-0.83

2,535

$3.34

717

$3.51

M07

Services by Other Medical Professionals

-0.87

830

$655.40

223

$1,341.16

E03

Encyclopedias or Other Sets of Reference Books

-0.88

243

$158.40

79

$189.75

F49

Easy-To-Prepare Canned or Packaged Foods excluding Fruits, Vegetables or Soups

-0.90

1,215

$21.42

367

$23.04

T11

Motor Vehicle Maintenance, Inspections, or Towing

-0.93

3,002

$293.30

834

$309.43

F25

Potatoes

-0.96

1,477

$4.52

441

$4.77

G13

Clothing Rental, Alterations or Repairs

-0.96

1,169

$123.01

383

$136.24

H08

Window Coverings such as Curtains, Drapes or Blinds

-0.99

2,444

$656.66

900

$728.76

R19

Photographer's Fees

-0.99

779

$468.72

221

$547.48

H07

Floor Coverings such as Hard Surface Tiling, Carpets or Scatter Rugs

-0.99

1,354

$2,227.78

422

$2,558.91

R32

Books Not Purchased Through Book Clubs

-1.01

1,383

$123.09

429

$945.08

T10

Motor Vehicle Body Work

-1.04

906

$1,145.34

283

$1,296.37

R12

Outboard Motors or Powered Sports Vehicles

-1.06

303

$10,226.43

102

$12,908.90

R28

Recreational Lessons or Instruction

-1.09

730

$581.20

202

$666.83

F29

Canned Fruits or Vegetables

-1.13

1,441

$27.75

467

$30.28

F07

Cookies

-1.16

2,011

$7.40

654

$10.96

R08

Pet Food

-1.17

2,577

$37.30

888

$39.35

M06

Eyeglasses or Eye Care

-1.18

2,469

$379.05

722

$407.79

F55

Beer, Ale, or Other Malt Beverages for Home Use

-1.19

1,123

$28.54

382

$31.73

H30

Powered Lawn or Garden Equipment or Other Outdoor Items

-1.20

1,389

$581.78

488

$681.28

T15

Parking Fees or Tolls

-1.21

1,381

$40.49

451

$46.96

G12

Shoe Repair or Other Shoe Services

-1.22

647

$55.26

177

$118.22

T13

 

-1.26

1,516

$1,458.98

603

$1,567.91

H06

Garbage or Trash Collection Service

-1.27

1,867

$256.27

567

$271.35

F27

Tomatoes

-1.27

1,336

$4.29

386

$4.71

R20

Film Development

-1.28

1,836

$41.71

565

$46.07

H02

Lodging Away From Home such as Hotels, Motels, or Vacation Rentals

-1.30

2,374

$1,049.04

793

$1,172.17

T08

Vehicle Parts or Accessories

-1.33

1,338

$298.18

478

$366.88

E12

Computer Software or Accessories

-1.34

1,270

$175.49

410

$208.35

M03

Medical Equipment, Supplies, Topicals or Dressings

-1.35

1,278

$55.55

414

$82.64

E01

College or University Level Textbooks

-1.40

876

$712.61

254

$950.05

F45

Seasonings, Spices, or Miscellaneous Baking Products such as Salt, Coat 'n Bake Products, Yeast, or Baking Chocolate

-1.43

1,018

$22.05

308

$25.87

T07

Tires

-1.43

1,803

$426.92

635

$452.89

F36

Sugar or Artificial Sweeteners

-1.45

1,641

$5.58

627

$6.09

H37

Moving, Storage, or Freight Services

-1.47

918

$1,599.32

352

$2,078.83

T16

Automobile Service Clubs

-1.51

1,637

$101.36

394

$122.64

F32

Carbonated Drinks

-1.52

1,509

$12.62

511

$13.92

H25

Non-Electric Kitchen Utensils, Cookingware or Bakeware

-1.55

1,204

$74.72

379

$87.04

R16

Hunting, Fishing, or Camping Equipment

-1.56

656

$284.69

213

$370.79

H11

Sofas, Slipcovers, or Decorative Pillows

-1.57

2,148

$1,319.65

792

$1,489.23

A21

Infants' or Toddlers' Underwear or Diapers

-1.57

418

$40.76

208

$55.50

F20

Miscellaneous Dairy Products including Yogurt, Powdered Milk, or Coffee Creamers

-1.58

1,741

$6.59

455

$7.38

H14

Infants' Furniture

-1.59

387

$473.21

175

$654.86

R17

Film or Film Development Supplies

-1.60

992

$29.25

307

$33.78

A09

Women's Outerwear

-1.62

1,854

$263.84

700

$305.62

F51

Limited Service Meals or Snacks

-1.63

2,785

$41.08

906

$47.91

E02

Elementary or High School Textbooks

-1.64

286

$206.43

99

$292.92

G19

Luggage, Briefcases, or Other Carrying Cases

-1.65

1,487

$190.17

436

$290.69

H31

Lawn or Garden Supplies or Insecticides

-1.74

2,611

$153.90

697

$191.23

F17

Milk

-1.74

3,380

$6.64

965

$7.24

E08

Delivery Services

-1.74

1,095

$86.79

346

$127.30

F24

Other Fresh Fruits

-1.75

1,321

$9.66

351

$11.08

G09

Legal Services

-1.77

765

$2,780.53

225

$5,261.30

E14

Home or Cellular Telephones, Answering Machines, or Other Phone Accessories

-1.79

1,778

$281.05

647

$503.45

F35

Powdered Drinks, Tea, Cocktail Mixes or Ice

-1.79

1,362

$8.69

409

$10.25

R06

Auto or Home Audio Equipment

-1.88

764

$319.40

251

$385.17

A10

Women's Dresses

-1.90

959

$204.51

329

$247.31

H12

Living Room Chairs or Living Room Tables

-1.90

1,269

$1,042.96

472

$1,223.59

F33

Non-Carbonated Juices or Drinks, Frozen or non-Frozen

-1.95

1,550

$11.48

443

$12.82

R03

VCRs, Camcorders, or Other Video Equipment

-1.96

1,095

$277.48

375

$385.91

F21

Apples

-1.99

1,390

$5.95

401

$6.84

F19

Ice Cream, Frozen Yogurt, or Flavored Ices

-2.00

1,732

$7.46

478

$8.46

F38

Jellies, Syrups, Honey, Molasses, Marshmallows, Icings, or Fudge Mixes

-2.01

1,490

$7.48

457

$8.59

A02

Men's Coats or Jackets

-2.06

1,085

$151.79

323

$180.86

F53

Food or Beverages from Vending Machines or Mobile Vendors

-2.07

764

$7.79

292

$9.46

T09

Motor Oil, Coolants, or Fluids

-2.13

1,578

$47.97

560

$55.12

A11

Women's Tops, Skirts, Pants, or Shorts

-2.14

1,765

$301.98

554

$361.41

F04

Bread

-2.17

4,457

$6.23

1,475

$6.66

H34

Other Disposable Products such as Plastic or Foil Wraps, Garbage Bags, Paper Plates, Batteries, or Light bulbs

-2.24

1,478

$23.87

526

$27.36

A03

Men's Socks, Underwear, Sleepwear or Bathrobes

-2.36

2,280

$58.12

844

$66.04

A19

Women's Footwear

-2.37

1,419

$131.69

435

$155.70

F41

Peanut Butter, or Cooking Fats and Oils

-2.39

1,205

$6.51

363

$7.69

R22

Video Game Hardware, Cartridges, Disks or Accessories

-2.47

1,133

$202.66

434

$248.20

F01

Flour or Prepared Flour Mixes

-2.53

1,591

$7.79

449

$11.40

H24

Dishes, Glassware, or Flatware

-2.54

1,576

$146.16

631

$184.03

R15

General Sports Equipment

-2.54

913

$246.82

301

$332.32

T18

Intracity Mass Transit

-2.59

457

$58.47

167

$77.00

G08

Haircuts or Other Personal Care Services

-2.61

2,524

$56.52

779

$67.74

H33

Paper Napkins, Paper Towels, Facial Tissue or Toilet Paper

-2.65

1,994

$25.82

688

$29.14

F30

Frozen Fruits or Vegetables

-2.67

2,305

$23.48

730

$26.96

A06

Men's Shirts, Sweaters, or Vests

-2.67

1,365

$174.95

419

$217.59

A17

Men's Footwear

-2.68

1,137

$114.84

356

$137.22

F58

Alcoholic Beverages Away From Home

-2.70

1,131

$39.76

378

$51.25

F09

Other Bakery Products including Frozen

-2.72

907

$8.54

267

$11.85

R21

Toys, Games, Hobbies, or Playground Equipment

-2.74

1,373

$264.70

456

$372.70

A01

Men's Suits or Blazers

-2.76

758

$458.71

226

$613.33

H28

Power Tools

-2.79

1,671

$466.60

497

$603.35

F46

Condiments, Sauces, or Gravies, such as Catsup, Mustard, Relishes, Tomato Sauces or Gravy Mixes

-2.81

1,384

$17.10

459

$20.81

H21

Small Electric Kitchen Appliances

-2.85

1,534

$73.30

508

$92.36

F22

Bananas

-2.87

1,770

$3.49

476

$4.33

G18

Stationery, School Supplies, or Giftwrap

-2.88

1,090

$45.04

415

$61.22

R05

Rental of Video Tapes or Video Discs

-2.90

1,439

$19.24

525

$23.68

E10

Long Distance Telephone Services

-2.94

1,630

$26.33

548

$31.38

A13

Women's Underwear or Nightwear

-3.03

1,989

$72.77

695

$87.46

H27

Paint, Wallpaper Tools, or Related Supplies

-3.07

1,725

$221.34

563

$314.63

F23

Fresh Citrus Fruits

-3.14

963

$6.15

301

$7.91

A04

Men's Accessories such as Ties, Belts, or Wallets

-3.21

1,572

$129.73

581

$187.94

F12

Lunchmeats, Hotdogs or Other Meats

-3.30

2,527

$12.26

755

$14.41

A07

Men's Pants, Jeans or Shorts

-3.34

1,332

$131.73

416

$178.07

G07

Cosmetics, Perfumes, or Bath and Nail Preparations

-3.37

2,198

$53.90

745

$64.77

F57

Deodorant, Feminine Hygiene Products, Suntan Lotions, or Footcare Products

-3.43

1,594

$31.15

586

$40.16

F14

Fresh Fish or Seafood

-3.44

1,318

$29.13

405

$37.06

E11

Personal Computers or Peripheral Equipment

-3.46

2,004

$1,305.50

675

$1,525.09

A14

Women's Hosiery or Accessories

-3.51

2,051

$87.50

773

$119.25

F43

Frozen Prepared Foods

-3.52

2,126

$25.25

666

$29.86

F11

Pork, Ham, or Breakfast Meats

-3.53

2,264

$15.61

617

$19.13

A08

Boys' Clothing or Accessories

-3.55

1,471

$231.16

530

$302.89

R02

Cable or Satellite Television Service

-3.57

3,205

$71.41

1,170

$77.58

F03

Rice, Pasta, or Cornmeal

-3.61

1,462

$8.12

453

$11.83

G06

Electric Personal Care Appliances such as Shavers or Hair Dryers

-3.73

1,500

$72.73

586

$125.30

A16

Girls' Clothing or Accessories

-3.76

1,446

$235.08

548

$304.63

A18

Boys' or Girls' Footwear

-3.97

820

$130.75

349

$171.91

F05

Fresh Biscuits, Rolls, Bagels, or Muffins

-3.98

2,084

$9.42

618

$12.22

F02

Breakfast Cereal

-3.99

1,888

$9.90

569

$12.50

F31

Dried or Other Processed Fruits or Vegetables

-4.05

979

$15.78

302

$23.48

A15

Women's Active Sportswear or Playwear

-4.06

2,086

$174.38

764

$235.65

F56

Dental or Shaving Products including Nonelectric Articles

-4.10

1,483

$20.13

440

$26.25

F55

Hair Products such as Shampoos, Sprays, Pins or Combs

-4.44

1,733

$15.49

655

$20.72

G20

Infants' Equipment such as Strollers, Car Seats, Bottles or Dishes

-4.50

913

$420.27

379

$706.37

H09

Household Linens, such as Kitchen or Bathroom Towels, Bedding, or Tablecloths

-4.60

1,242

$159.26

512

$261.29

F13

Chicken or Other Poultry including Turkey

-4.67

3,212

$20.08

1,009

$25.22

E09

Local Telephone Service

-4.78

4,000

$43.88

1,449

$48.20

H32

Household Laundry and Cleaning Products or Supplies

-4.80

1,882

$38.02

663

$47.99

G11

Laundry or Dry Cleaning Services

-5.06

1,611

$46.31

542

$62.97

A20

Infants' or Toddlers' Clothing or Accessories

-5.16

1,406

$169.38

485

$251.59

E16

Cellular Telephone Service

-5.59

3,199

$87.04

1,187

$102.19


Appendix B - Comparison of POPSCAT Expenditure Means for Cell Phone-Only and Landline/Cell Phone and Landline-Only Telephone Consumer Units in the Consumer Expenditure Survey 8

POPSCAT

POPSCAT Title

T Statistic

Cell Phone-Only Consumer Unit Expenditure Reports

Cell Phone-Only Consumer Unit Expenditure Mean

Landline and Cell Phone/Landline-Only Consumer Unit Expenditure Reports

Landline and Cell Phone/Landline-Only Consumer Unit Expenditure Mean

E14

Home or Cellular Telephones, Answering Machines, or Other Phone Accessories

-2.30

305

$123.53

2,235

$106.38

T19

Taxi Fare

-1.25

419

$90.11

2,934

$78.30

E03

Encyclopedias or Other Sets of Reference Books

-0.91

5

$152.20

47

$77.81

G20

Infants' Equipment such as Strollers, Car Seats, Bottles or Dishes

-0.88

55

$161.16

311

$135.28

E15

Calculators, Typewriters, or Other Information Processing Equipment

-0.83

36

$113.78

348

$83.98

R31

Books Purchased Through Book Clubs

-0.78

41

$96.61

598

$75.75

H28

Power Tools

-0.66

111

$267.16

1,024

$237.63

H37

Moving, Storage, or Freight Services

-0.60

138

$735.43

670

$635.63

T08

Vehicle Parts or Accessories

-0.42

579

$138.60

3,916

$131.87

R04

Blank or Pre-recorded Video Cassettes and Video Discs

-0.34

815

$91.16

4,976

$88.77

A17

Men's Footwear

-0.30

696

$119.10

4,733

$117.53

H31

Lawn or Garden Supplies or Insecticides

-0.17

29

$45.30

739

$43.30

H14

Infants' Furniture

-0.17

59

$287.49

317

$278.16

R14

Bicycles or Bicycling Accessories

-0.16

97

$249.75

683

$243.50

R19

Photographer's Fees

-0.15

105

$260.29

1,035

$251.05

T18

Intracity Mass Transit

0.02

554

$221.71

3,809

$222.14

E05

Tuition or Fixed Fees for Private Elementary or High Schools

0.07

31

$4,117.94

567

$4,254.44

R22

Video Game Hardware, Cartridges, Disks or Accessories

0.10

308

$186.43

2,150

$187.75

T09

Motor Oil, Coolants, or Fluids

0.14

1,206

$17.72

8,026

$17.88

A12

Women's Suits or Suit Components

0.26

84

$239.45

979

$252.01

R24

Musical Instruments or Musical Accessories

0.38

56

$318.13

535

$343.67

T14

Local Vehicle Registration

0.39

82

$111.11

728

$117.13

A10

Women's Dresses

0.51

294

$179.87

2,861

$193.15

G13

Clothing Rental, Alterations or Repairs

0.51

158

$65.85

1,363

$69.76

H29

Non-powered Tools, or Miscellaneous Hardware

0.62

169

$253.59

1,490

$298.94

R10

Pet Services

0.63

136

$202.75

1,716

$229.76

T10

Motor Vehicle Body Work

0.70

64

$558.63

565

$632.22

A07

Men's Pants, Jeans or Shorts

0.70

615

$126.42

4,725

$131.85

G14

Watch or Jewelry Repair

0.88

65

$42.54

968

$53.16

T02

New Motorcycles

0.92

10

$8,894.80

56

$10,471.70

A02

Men's Coats or Jackets

0.93

243

$116.77

1,739

$124.58

A14

Women's Hosiery or Accessories

0.94

483

$61.52

4,157

$69.88

G15

Checking Accounts, Credit Card Fees, or Other Bank Services

1.12

699

$64.17

4,361

$68.19

A01

Men's Suits or Blazers

1.15

131

$287.13

1,292

$337.89

H18

Washers or Dryers

1.27

101

$715.87

904

$820.14

G09

Legal Services

1.32

119

$1,470.36

913

$1,929.84

T17

Ship Travel or Passenger Cruises

1.45

104

$425.36

1,143

$597.42

A04

Men's Accessories such as Ties, Belts, or Wallets

1.46

230

$45.93

1,603

$55.91

G12

Shoe Repair or Other Shoe Services

1.46

46

$35.57

452

$47.85

A05

Men's Active Sportswear such as Exercise Apparel or Bathing Suits

1.46

138

$64.91

1,190

$75.08

A23

Jewelry

1.49

413

$403.97

3,217

$505.38

A21

Infants' or Toddlers' Underwear or Diapers

1.52

318

$168.32

1,976

$184.10

H25

Non-Electric Kitchen Utensils, Cookingware or Bakeware

1.53

231

$67.13

1,591

$88.64

R23

Sewing Machines, Fabric or Sewing Supplies

1.60

188

$83.11

2,021

$130.41

H90

 

1.61

26

$2,193.65

272

$2,834.78

H27

Paint, Wallpaper Tools, or Related Supplies

1.67

104

$155.53

1,011

$194.50

E04

Tuition or Fixed Fees for a College or University

1.83

302

$3,391.51

1,534

$4,031.03

A03

Men's Socks, Underwear, Sleepwear or Bathrobes

1.88

487

$39.67

3,571

$44.45

R13

Unpowered Boats or Trailers

1.88

7

$4,525.86

71

$8,135.69

E12

Computer Software or Accessories

1.98

230

$115.68

1,820

$141.69

A13

Women's Underwear or Nightwear

2.00

492

$68.63

4,679

$77.25

T04

Car, Truck, or Van Rental

2.05

185

$289.94

1,377

$360.39

H15

Outdoor Furniture

2.22

58

$273.69

565

$455.81

H04

Other Household Fuels For Heating or Cooking such as Propane, Firewood, or Coal

2.29

109

$264.50

1,486

$356.90

R18

Cameras or Other Photographic Equipment excluding Film

2.35

170

$254.63

1,274

$316.70

R06

Auto or Home Audio Equipment

2.39

245

$191.31

1,838

$244.66

R16

Hunting, Fishing, or Camping Equipment

2.44

145

$172.80

959

$252.97

E07

Tuition or Fixed Fees for Technical or Vocational Schools

2.47

29

$588.52

299

$1,133.46

A22

Watches

2.51

164

$97.20

1,717

$150.10

R17

Film or Film Development Supplies

2.53

218

$25.44

2,259

$30.79

G02

Tobacco Products Other Than Cigarettes

2.58

154

$232.40

698

$307.16

R11

Veterinarian Services

2.63

259

$315.65

2,925

$396.80

H39

Reupholstery of Household Furniture

2.70

17

$168.88

227

$388.74

R07

Prerecorded or Blank Audio Tapes, CDs or Records

2.71

857

$68.16

5,357

$76.75

H26

Indoor Plants or Fresh Cut Flowers

2.80

465

$92.60

4,889

$132.76

H38

Major Appliance Repair

2.83

58

$143.52

1,573

$201.01

A20

Infants' or Toddlers' Clothing or Accessories

2.88

471

$104.50

3,722

$125.26

E10

Long Distance Telephone Services

2.88

290

$113.54

17,590

$156.30

R29

Single Copy Newspapers or Magazines

2.89

743

$29.72

4,766

$34.72

R03

VCRs, Camcorders, or Other Video Equipment

2.96

161

$130.07

1,317

$181.14

R01

Televisions

2.97

270

$721.75

1,899

$883.25

T12

Motor Vehicle Repair

3.01

601

$534.95

4,858

$641.59

G10

Funeral Services

3.12

40

$873.28

652

$1,654.44

G16

Tax Return Preparation or Other Accounting Services

3.17

217

$183.37

2,398

$364.16

H17

Refrigerators or Home Freezers

3.18

93

$687.94

817

$906.56

A19

Women's Footwear

3.30

848

$105.95

6,731

$123.01

H23

Household Decorative Items Including Clocks or Lamps

3.30

472

$98.60

3,674

$233.97

H22

Heating or Cooling Equipment or Home Safety Devices

3.30

229

$101.32

1,677

$148.96

H24

Dishes, Glassware, or Flatware

3.35

518

$58.44

3,046

$81.58

A15

Women's Active Sportswear or Playwear

3.36

203

$70.67

1,804

$91.53

G06

Electric Personal Care Appliances such as Shavers or Hair Dryers

3.38

241

$40.85

1,464

$51.71

F54

Catered Events or Board

3.40

269

$685.31

1,456

$1,087.36

R09

Pets, Pet Supplies or Accessories

3.53

722

$206.51

5,886

$254.30

H07

Floor Coverings such as Hard Surface Tiling, Carpets or Scatter Rugs

3.54

227

$456.19

1,781

$808.87

H30

Powered Lawn or Garden Equipment or Other Outdoor Items

3.61

128

$272.81

1,389

$483.68

R05

Rental of Video Tapes or Video Discs

3.71

1,039

$55.12

5,453

$63.55

R12

Outboard Motors or Powered Sports Vehicles

3.72

10

$30.70

157

$5,947.78

E11

Personal Computers or Peripheral Equipment

3.72

324

$574.97

2,405

$714.09

T95

Train Fares

3.75

202

$83.78

1,770

$132.52

G19

Luggage, Briefcases, or Other Carrying Cases

3.77

63

$82.67

767

$123.77

H21

Small Electric Kitchen Appliances

3.82

422

$54.25

3,089

$73.77

E01

College or University Level Textbooks

3.89

325

$396.85

1,212

$496.55

H40

Inside Home Maintenance or Repair

4.06

67

$698.43

1,224

$1,223.39

E02

Elementary or High School Textbooks

4.08

131

$98.06

1,496

$142.61

H10

Bedroom Furniture Including Mattresses and Springs

4.15

251

$743.90

1,579

$1,045.40

T94

Bus Fares

4.18

197

$48.30

1,813

$72.44

T16

Automobile Service Clubs

4.21

122

$79.51

2,247

$105.38

A06

Men's Shirts, Sweaters, or Vests

4.27

963

$107.74

6,351

$127.05

H11

Sofas, Slipcovers, or Decorative Pillows

4.37

270

$564.95

1,582

$870.84

H13

Kitchen or Dining Room Furniture

4.58

123

$423.15

639

$883.05

A18

Boys' or Girls' Footwear

4.66

436

$94.23

3,666

$120.31

H12

Living Room Chairs or Living Room Tables

4.82

175

$342.34

1,274

$593.91

E06

Day Care Providers including Nursery Schools

4.91

266

$1,613.26

1,857

$2,405.14

H20

Vacuums or Other Electric Floor Cleaning Equipment

5.01

165

$107.14

965

$182.65

T92

State Vehicle Reg., License, and Taxes

5.07

932

$114.83

7,447

$141.45

R20

Film Development

5.16

421

$41.92

3,531

$57.65

G01

Cigarettes

5.29

854

$636.28

3,980

$779.31

H08

Window Coverings such as Curtains, Drapes or Blinds

5.41

250

$149.83

1,789

$348.49

T07

Tires

5.50

405

$301.54

3,140

$384.39

R15

General Sports Equipment

5.67

392

$189.55

2,801

$293.13

T03

Leased Cars, Trucks, or Vans

5.82

96

$2,398.76

893

$3,944.38

A09

Women's Outerwear

5.86

292

$91.55

2,754

$132.58

H03

Fuel Oil

5.92

52

$621.08

1,029

$1,087.09

T15

Parking Fees or Tolls

6.00

851

$84.13

6,245

$120.03

A16

Girls' Clothing or Accessories

6.03

386

$176.84

3,725

$255.33

R27

Admissions to Sporting Events

6.14

686

$92.06

4,600

$160.05

A08

Boys' Clothing or Accessories

6.20

355

$145.62

3,524

$205.06

R28

Recreational Lessons or Instruction

6.48

151

$382.71

2,043

$728.17

G11

Laundry or Dry Cleaning Services

6.49

1,345

$139.94

7,266

$176.16

R21

Toys, Games, Hobbies, or Playground Equipment

6.63

683

$166.20

5,045

$237.02

E16

 

6.64

2,919

$494.57

10,590

$559.60

H09

Household Linens, such as Kitchen or Bathroom Towels, Bedding, or Tablecloths

6.69

854

$97.43

5,776

$131.73

H36

Gardening or Lawn Care Services

6.93

226

$157.38

4,145

$361.95

H19

Stoves, Ovens or Microwave Ovens

7.64

179

$213.72

1,077

$535.44

H06

Garbage or Trash Collection Service

7.67

784

$121.79

8,325

$164.34

H16

Occasional Furniture such as Bookcases, Desks, or Ottomans

8.37

197

$224.77

1,313

$561.94

A11

Women's Tops, Skirts, Pants, or Shorts

8.48

1,191

$186.50

9,397

$254.46

H35

Housekeeping Services

9.52

68

$416.32

1,586

$1,006.59

E13

Online or Other Information Services

9.53

1,196

$162.79

10,878

$202.60

T93

Airline Fares

9.54

490

$685.03

3,985

$1,105.83

R25

Club Membership Dues such as Recreational Clubs, Fraternal or Civic Organizations, or Fees Paid for Participant Sports

10.17

948

$240.07

7,019

$437.70

R32

Books Not Purchased Through Book Clubs

10.31

740

$72.63

5,469

$114.51

T11

Motor Vehicle Maintenance, Inspections, or Towing

11.08

1,573

$143.84

11,212

$216.36

R26

Admissions such as Movies, Concerts, or Theme Parks

13.03

1,441

$137.19

8,562

$228.55

H02

Lodging Away From Home such as Hotels, Motels, or Vacation Rentals

13.08

587

$454.85

5,355

$894.28

R30

Newspaper or Magazine Subscriptions

13.49

362

$58.36

6,094

$103.39

R02

Cable or Satellite Television Service

14.71

1,791

$349.02

14,239

$451.87

H05

Residential Water or Sewer Service

18.75

1,220

$211.09

11,411

$326.19

G08

Haircuts or Other Personal Care Services

19.88

1,870

$153.88

13,219

$259.49

T05

Gasoline, Diesel, or Alternative Fuels

21.44

2,648

$1,093.67

16,207

$1,584.53


1 The BLS defines a consumer unit or CU as a person living alone or a group of two or more persons who are related by blood, marriage, or other living arrangement; or a group of two or more persons who share major living expenses.

2 Response rate (see section 1) is calculated according to OMB’s response rate definition:

Unweighted Response Rate = C a

C + R + NC + O + e(U)

3 “Household Telephone Service and Usage Patterns in the United States in 2004: Implications for Telephone Samples,” Clyde Tucker, J. Michael Brick, Brian Meekins, Public Opinion Quarterly, Vol. 71, No. 1, Spring 2007, pp. 3-22.

4 “Wireless Substitution: State-level Estimates From the National Health Interview Survey, January-December 2007”, Stephen J. Blumberg, Ph.D.; Julian V. Luke, Gestur Davidson Ph.D.; Michael E. Davern, Ph.D; Tzy-Chyi Yu, M.H.A., Ph.D.; Karne Soderberg, M.S., National Health Statistics Reports, Number 14, March 11, 2009

5 Q042 experiences a rise in non-contacts due to the implementation of WEB-CATI software and the AAPOR classification method.

6 A Shapiro-Wilk statistic was calculated to determine the normality of the samples of expenditures by POPSCAT for each group. Only one sample (New Cars and Trucks for the cell phone-only population) failed to pass the normality test assuming α = 0.05.

7 Sorted by T-Statistic, 90% Significance Level used

8 Sorted by T-Statistic, 90% Significance Level used

26

File Typeapplication/msword
File TitleAssessing nonresponse bias in the Telephone Point of Purchase Survey:
AuthorSaxton_M
Last Modified Bysaxton_m
File Modified2012-03-09
File Created2009-04-20

© 2024 OMB.report | Privacy Policy