Compare methods

	Lost Letter Technique	False Consensus Paradigm	Unmatched Count Technique
Field	Social Psychology	Social Psychology	Social Psychology
Family	Process / pipeline	Process / pipeline	Process / pipeline
Year of origin	1965	1977	2010
Originator	Stanley Milgram, Leon Mann & Susan Harter	Lee Ross, David Greene & Pamela House	Survey-methodology tradition; Holbrook & Krosnick (validation)
Type	Unobtrusive field measure of attitudes	Experimental paradigm for social-perception bias	Indirect survey technique for sensitive questions
Seminal source	Milgram, S., Mann, L., & Harter, S. (1965). The lost-letter technique: A tool of social research. Public Opinion Quarterly, 29(3), 437-438.	Ross, L., Greene, D., & House, P. (1977). The 'false consensus effect': An egocentric bias in social perception and attribution processes. Journal of Experimental Social Psychology, 13(3), 279-301.	Holbrook, A. L., & Krosnick, J. A. (2010). Social desirability bias in voter turnout reports: Tests using the item count technique. Public Opinion Quarterly, 74(1), 37-67.
Aliases	Lost-Letter Technique, Dropped Letter Method, Return-Rate Attitude Measure	False Consensus Effect, Egocentric Projection Paradigm, Consensus Estimation Task	Item Count Technique, List Experiment, Unmatched Block Design
Related	3	3	3
Summary	The lost letter technique, introduced by Milgram, Mann, and Harter in 1965, is an unobtrusive field method for measuring community attitudes by exploiting a small act of everyday helping. Researchers distribute stamped, addressed envelopes in public places as if they had been accidentally dropped, with the letters addressed to different organizations representing varying causes (for example, a neutral individual versus a politically charged group). A passerby who finds a letter must decide whether to mail it, ignore it, or destroy it, and the proportion of letters returned for each addressee serves as an index of public sentiment toward that cause -- letters addressed to favored organizations are mailed more often than those to disfavored ones. Because finders do not know they are participating in a study, the measure sidesteps social-desirability bias and yields a behavioral, aggregate indicator of attitudes that complements self-report surveys.	The false consensus paradigm, established by Ross, Greene, and House in 1977, demonstrates a pervasive bias in social perception: people overestimate the extent to which others share their own choices, beliefs, and behaviors. In the canonical procedure, participants indicate their own position on some issue or choice -- famously, whether they would walk around campus wearing a sandwich-board sign -- and then estimate what proportion of their peers would do the same. The signature finding is that those who choose a given option estimate that option to be more common than do those who reject it, so each group projects its own response onto others. Ross and colleagues also showed that people view their own responses as relatively common and unrevealing of personality while seeing differing responses as uncommon and diagnostic of others' traits. The paradigm became a foundational demonstration of egocentric bias in social judgment and attribution.	The unmatched count technique (also called the item count technique or list experiment) is an indirect survey method for estimating the prevalence of sensitive attitudes or behaviors while protecting respondents' privacy. Respondents are randomly assigned to one of two versions of a question. The control group sees a list of several non-sensitive items and reports only how many of them apply to them; the treatment group sees the same list plus one additional sensitive item and likewise reports only the count. Because respondents report a number rather than which items apply, no one's answer reveals their stance on the sensitive item. The estimated prevalence of the sensitive attribute is simply the difference in mean counts between the treatment and control groups. By breaking the link between an individual and the sensitive item, the technique reduces social-desirability bias for topics like prejudice, illegal behavior, or stigmatized attitudes, as documented in validation work by Holbrook and Krosnick.