SOMA OMB Supporting Statement 2-6-17_PartB

Supporting Statement for Paperwork Reduction Act Submission

for the Survey of Market Absorption

of New Multifamily Units (SOMA)

(OMB 2528-0013)

B. Collections of Information Employing Statistical Methods

1. Universe and Respondent Selection

The buildings selected for SOMA are those included in the Census Bureau's Survey of Construction (SOC). For SOC, the United States is first divided into primary sampling units (PSU's) which are sampled based on population. Next, a sample of permit-issuing places is selected within each sample PSU. Finally, all buildings with five or more units within sampled places as well as a subsample of buildings with one to four units are selected for the SOC sample.

The respondent universe consists of builders, building managers, rental agents, sales agents, and landlords of newly completed real estate developments or buildings containing five or more units.

2. Procedures for Collecting Information

Each month SOMA selects its sample from the SOC records that reported five or more units. If there are more than 1,000 buildings completed in a month, a subsample of buildings is selected. The subsampling rate is dependent on the total number of buildings completed, but the total number of buildings in sample each month can never exceed 1,000.

Information is collected quarterly on the proportion of units absorbed 3, 6, 9, and 12 months after completion is obtained for units in buildings selected in a given quarter in each of the next four quarters.

Unbiased quarterly estimates are formed by multiplying the counts for each building by its base weight (the inverse of its probability of selection) and then summing over all buildings. The final estimate is then obtained by multiplying the unbiased estimate by a ratio estimate factor.

3. Methods to Maximize Response

The response rate is above 90 percent and is expected to remain at that level. Due to the high response rate, only normal data collection procedures are followed for nonresponse cases, i.e., supervisory personnel contact reluctant respondents.

4. Test of Procedures or Methods

Describe any tests of procedures or methods to be undertaken. Testing is encouraged as an effective means of refining collections of information to minimize burden and improve utility. Tests must be approved if they call for answers to identical questions from 10 or more respondents. A proposed test or set of test may be submitted for approval separately or in combination with the main collection of information

In 2014, the SOMA CAPI instrument was developed and thoroughly tested. Testing included instrument testing, an initial systems test, and a final systems test or verification test. Instrument testing tests different pathways through the instrument, ensuring that questions and response categories appear as intended and that skip patterns are correct. Extensive instrument test was conducted by Census Headquarters staff. In an effort to seek the opinions of actual users, a few local Census Field Representatives (FRs) were invited to Census Headquarters to test the instrument. Feedback was positive and the FRs welcomed the change to an automated instrument. Systems tests test all of the systems that interact with the CAPI instrument, but also allows for continued testing of the instrument. Problems were recorded and fixed during the initial systems test and retested during the verification test. Since then, only minor changes have been made to the instrument. We performed systems testing prior to the April 2015 and April 2016 instrument releases.

5. Contacts for Statistical Aspects and Data Collection

The individuals to contact are:

Tamara Cole

Survey Director, SOMA

Bureau of the Census

Phone: (301) 763-4665

Medell E. Ford III

Chief, Housing and Health Surveys Branch

Field Division

Bureau of the Census

Phone: (301) 763-2185

Stephen Ash

Lead Scientist, SOMA

Demographic Statistical Methods Division

Bureau of the Census

Phone: (301) 763- 4294

List of Attachments

SOMA Items Booklet

USC 1701Z citation

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