“Heads or tails?”—A reachability bias in binary choice.

Abstract

When asked to mentally simulate coin tosses, people generate sequences that differ systematically from those generated by fair coins. It has been rarely noted that this divergence is apparent already in the very 1st mental toss. Analysis of several existing data sets reveals that about 80% of respondents start their sequence with Heads. We attributed this to the linguistic convention describing coin toss outcomes as "Heads or Tails," not vice versa. However, our subsequent experiments found the "first-toss" bias reversible under minor changes in the experimental setup, such as mentioning Tails before Heads in the instructions. We offer a comprehensive account in terms of a novel response bias, which we call reachability. It is more general than the 1st-toss bias, and it reflects the relative ease of reaching 1 option compared to its alternative in any binary choice context. When faced with a choice between 2 options (e.g., Heads and Tails, when "tossing" mental coins), whichever of the 2 is presented first by the choice architecture (hence, is more reachable) will be favored. This bias has far-reaching implications extending well beyond the context of randomness cognition; in particular, to binary surveys (e.g., accept vs. reject) and tests (e.g., True-False). In binary choice, there is an advantage to what presents first.

Cognitive Style and Frame Susceptibility in Decision-Making

“…Nevertheless, in each experiment, the proportion of choices that were frame-consistent was greater when the frame-consistent choice was presented first. These non-significant differences are in the same direction as that reported by Schwitzgebel and Cushman (2015) , and also in line with the reachability bias ( Bar-Hillel et al, 2014 ). Moreover, if we combine our samples, the effect approaches significance using a one-tailed test: 63.1% choose the frame-consistent choice when that option was presented initially versus 56.1% when that option was presented last, p = 0.057 by Fisher’s exact one-sided test.…”

“…We manipulated option order as recommended by Fagley and Miller (1997) . In most studies, the certain option is presented first, yet Bar-Hillel et al (2014) have shown a “reachability bias” in response-option selection favoring the option presented first. Kühberger and Gradl (2013) found that although option order had no effect on choice in the positive-frame condition, a greater proportion of participants in the negative-frame condition chose the uncertain option when it was presented after the certain option than when it was presented initially, contrary to the reachability bias.…”

To be an honest person or not to be a cheater: Replicating the effect of messages relating to the self on unethical behaviour

“…Participants received NIS 2 (about $0.40) voucher to the campus cafeteria for every toss landing on tails . We chose tails in Hebrew to correspond with heads in English in reachability (Bar‐Hillel, Peer, & Acquisti, ). Participants were screened to be native Hebrew speakers.…”

Menu positions influence soft drink selection at touchscreen kiosks

“…This order effect is realized by at least two mechanisms (Bar‐Hillel, ; Rodway, Schepman, & Thoma, ). The first mechanism is physical reachability (Bar‐Hillel, Peer, & Acquisti, ). The idea is that ceteris paribus, items located in the most reachable location are the most likely to be selected.…”