2.Study 1aThe objective of study 1a was to test if consumers were more likely to purchase a target option in the presence of an incidental out-of-stock option, relative to a control condition in which an out-of-stock option was absent. To ascertain that the hypothesized effect was independent of the particular attribute levels of the OOS option, we included two OOS present conditions, such that in each, one of the two attributes was better and one was worse than those of the target option.