Seam Effects in Quantitative Responses

• Activity Number: 397
• Type: Topic Contributed
• Date/Time: Tuesday, August 3, 2010 : 2:00 PM to 3:50 PM
• Sponsor: Section on Survey Research Methods
• Author(s): Frederick Conrad*+ and Lance Rips and Scott Fricker
• Companies: Institute for Social Research and Northwestern University and Bureau of Labor Statistics
• Keywords: seam effects ; longitudinal surveys ; dependent interviewing

Abstract

The seam effect is an artifact of panel surveys in which respondents are interviewed every few months and asked for data about each of the intervening months. We used an experimental method to examine the seam effect for quantitative questions about dollar amounts. Our studies produced robust seam effects, accompanied by forgetting of correct amounts and constant responding (no change between months) within the reference periods. The results also showed decreases in the seam effect when questions about the same topic appeared in different parts of the interview. In some conditions, dependent interviewing also reduced the size of the seam effect. Neither manipulation, however, improved the overall accuracy of responses. Dependent feedback may encourage respondents to make less drastic changes at the seam but perpetuate incorrect responses from one reference period to the next.