Open materials and data for Greenberg & Spiller, “Opportunity Cost Neglect Attenuates the Effect of Choices on Preferences,” Psychological Science. Stimuli are provided in 3 .docx files: 1. Experiment 1: GreenbergSpillerExp1.docx; 2. Experiment 2: GreenbergSpillerExp2.docx; and 3. Experiment 3: GreenbergSpillerExp3.docx. Data are provided in 3 .csv files: 1. Experiment 1: GreenbergSpillerExp1.csv; 2. Experiment 2: GreenbergSpillerExp2.csv; and 3. Experiment 3: GreenbergSpillerExp3.csv. Variable interpretations are presented in codebook.xlsx (with separate sheets for Experiment 1, Experiment 2, and Experiment 3). Two steps were taken to ensure participant anonymity for posting: 1. In each study, Amazon Mechanical Turk ID (“MID”) was converted to an observation number and IP addresses were removed. 2. To ensure no participant may have inadvertently identified herself or himself (explicitly or not) via open-ended text, out of an abundance of caution, we have also masked the open-ended text field at the end of the study (“Check” in Experiments 1 and 2, “CheckRCR” and “CheckRRC” in Experiment 3). We kept the codes for individual words and the aggregate value. There are five such codes: Check100, CheckVisa, CheckGift, CheckCard, and CheckRight. The first four are TRUE if the term (100, Visa, Gift, Card) was present and FALSE if not (case did not matter). CheckRight took a value of 1 if any of those values were TRUE and 0 otherwise. Data from all participants who completed each study are included. In Experiment 3, there were two participants who completed the study a second time after completing it once (as indicated by their Amazon Mechanical Turk ID), so they are not part of the dataset. To ensure complete transparency, their data are included in the DuplicateParticipantsGreenbergSpillerExp3.csv file.