Additional OMB Questions

Supplementary Information:

FHWA Exploratory Advanced Research (EAR) Program sponsored project titled "Effects of Automated Transit and Pedestrian/Bicycling Facilities on Urban Travel Patterns

OMB Follow-up Questions

The rationale for selecting the four neighborhoods for the study. “OMB initially questioned the choice of Chicago for the case studies, but I believe we were able to satisfy them there.  I noted our desire to examine neighborhoods with access to the rail transit network as well as different socioeconomic characteristics, but the OMB staff wanted a more detailed response, apparently to justify why four neighborhoods were included in the plan and how they were different”. 

The four neighborhoods were the product of a two-by-two design:  more affluent (Skokie, Evanston) and less affluent (Cicero, Pilsen), and auto-oriented in urban form (Cicero, Skokie) and more transit/pedestrian-oriented in form (Pilsen, Evanston).  The underlying premise that that urban form and household income are two of the most important determinants of mode choice; this design ensures that a) we have variability in each; and b) we can observe the effect of each separately.

The methodology for normalizing responses to address differences between stated and actual preferences.  “OMB wanted specific information as to how this would be done”.

Responses from stated preference will be normalized to the revealed preference data.  That is, the stated-preference scenarios contain among them a status-quo scenario.  In principle, stated-preference responses to the status quo scenario should match current behavior.  We expect that there will be bias, however, with stated behavior ostensibly showing higher rates of walking, cycling, and transit use than revealed behavior.   Estimated rates of use of travel modes for future scenarios will be reduced by the extent of the bias observed in the gap between current behavior and stated behavior under the status quo scenarios.

Whether a Spanish language version of the questionnaire (and other materials) will be used.  “The research protocol document noted that the initial letter would include English and Spanish, but did not note whether other materials would also be printed in both languages. I pointed out that the interviewers would be fluent in Spanish as needed”.

Yes, Spanish-language versions of all materials will be provided.  The Survey Research Lab will be developing these translations, as required for Institutional Review Board approval.

How to justify the $50 response incentive or whether a much smaller incentive should instead be used. 
This study is unique in that it requires participants to complete four separate elements that are each independently burdensome, and taken as a whole, are very burdensome.  After respondents return the response letter and indicate their interest in participating in the study, they are mailed a study packet that includes a travel diary and a booklet with images and worksheets.  The first thing we ask respondents to do is to spend time completing a detailed, five-page travel diary in advance of the telephone interview.  Then, we ask them to complete a telephone interview.  Finally, during the phone interview, respondents are asked to fill in values on the six separate worksheets that we provide in the booklet.  These values are calculated based on information the respondent provides during the phone interview using the travel diary, so they cannot be pre-filled.  Once the respondent fills in the values, they are asked to answer questions based on the images and worksheets.  In appreciation for the considerable amount of effort we are asking respondents to put into this study, we propose offering a $50 incentive. Research has shown that incentives increase cooperation and there is some evidence that they reduce the number of calls required on sample cases which reduces interviewer effort and cost. (Groves, R.M., and Couper, M.P. (1998). Nonresponse in Household Interview Surveys, New York: Wiley.)  The $50 incentive used in this study is appropriate for helping us achieve a reasonable participation rate.  The results of the pretest indicate that even with the $50 incentive, the participation rate for this study is somewhat low at 9%.  The participation rates are detailed in the table below.

Table 2. Final Disposition of Sample, overall and by neighborhood, pretest

Code	Disposition	Overall			Cicero (STID 1)		Pilsen (STID 2)		Evanston (STID 3)		Skokie (STID 4)
		#	%		#	%	#	%	#	%	#	%
1	Completed interview (called)	9		9.0%	1	4.0%	1	4.0%	4	16.0%	3	12.0%
31	Answering machine/answering service (called)	1		1.0%	1	4.0%	0	0.0%	0	0.0%	0	0.0%
40	Final refusal before screener completed (called)	2		2.0%	0	0.0%	2	8.0%	0	0.0%	0	0.0%
57	Unable to locate (called)	2		2.0%	1	4.0%	1	4.0%	0	0.0%	0	0.0%
60	Other eligible (called)	1		1.0%	0	0.0%	0	0.0%	0	0.0%	1	4.0%
2	Eligible, received response to late to call (not called)	2		2.0%	0	0.0%	1	4.0%	0	0.0%	1	4.0%
71	Ineligible, did not live at sampled address (not called)	1		1.0%	1	4.0%	0	0.0%	0	0.0%	0	0.0%
41	Refused (not called)	1		1.0%	0	0.0%	0	0.0%	0	0.0%	1	4.0%
	No response to initial mailing	81		81.0%	21	84.0%	20	80.0%	21	84.0%	19	76.0%
Total		100		100.0%	25	100.0%	25	100.0%	25	100.0%	25	100.0%