**REPLICATION INFORMATION** We are a group of undergraduate student researchers from Masaryk University, Czech Republic. Our aim was to replicate Turri, Buckwalter and Blouw's (2015) study which explores the issue of Justified True Belief (JTB), trying to establish in which situatons and under which circumstances people attribute agent's success to knowledge and when to luck. The abstract of the study can be found below. We carried out this replication study as a part of the Accelerated CREP Project. Following deviations from the preprint (Hall et al., 2018) were conducted: a) omission of some demographic questions and addition of others, b) altered version of visual analogue scale because of software issues, c) slightly different survey flow (first vignette was not fixed to Darrel but randomly assigned) and d) inclusion of a set of additional questions about the participants' study experience at the end of the experimental session. Please see component Materials for more detailed description of these deviations. **Important note: We accidentally swapped Gerald knowledge control vignette for ignorance control vignette. I.e. there were two Gerald ignorance control vignettes in our study and no Gerald knowledge control vignette.** Regarding the data collection, we employed a convenience sampling, selected mostly our acquaintances and members of various social media groups. The data for the project was gathered until few days before the official end of data collection period. We aimed to reach at least 100 participants and our analysis entered 111 participants. The sample size consists of both university students and non-university participants. The study was held online via the platform Qualtrics and participants were not compensated for the participation in the study. **PROCEDURE** First, participants were given an informed consent form, which included the following statement used by Turri et al. (2015): “We hope that our results will add to scientific knowledge about how language works.” Respondents expressed their consent with voluntary participation in the survey by clicking on the button with an arrow. Once they have provided their informed consent, participants were instructed how to proceed though the questionnaire and then presented with three vignettes in random order. Each vignette was randomly assigned to a belief condition and counter-balanced so that each participant experiences all three vignettes (“Darrel”, “Gerald”, and “Emma”) and all three belief conditions (knowledge control, Gettier case, and ignorance control) once. After participants have read each assigned vignette, they were asked to respond to several questions, one at a time, before moving on to the next vignette. Participants weren't allowed to return to the previous item. As in Turri et al. (2015), participants first responded to a knowledge attribution question followed by comprehension question to control for understanding and, finally, they answered a question about whether it was reasonable or unreasonable for the protagonist to believe what they believed. To measure the knowledge attribution and reasonableness we used a visual analogue scale (see Materials for ) and for comprehension control a binary response format. In addition, consistently with the preprint, after these three items we asked an exploratory binary knowledge attribution question and an additional exploratory question related to the perception of luck and ability of the protagonist. Subsequently, after the completion of all questions for each vignette, participants were asked to answer several control, study experience and demographic questions. Control variables encompassed the language proficiency and a set of debriefing questions to check for explicit knowledge of the hypotheses. Demographics included the participant age, gender and years of education. Deviating from the preprint, we included a set of additional questions about the participants' study experience. Finally, as a part of debriefing, participants were provided with a short clarification of the purpose of the present study. (For a visual demonstration of the study tasks, please see a Video of Procedure, and for detailed description of materials and offline questionnaire, please see component Materials.) **STUDENT RESEARCHERS** Gabriela Kalistová Bc. Denisa Prchalová Bc. Libor Potočár **PROJECT SUPERVISOR** Mgr. Jaroslav Gottfried **PROJECT NUMBER** AC1938 **TURRI ET AL. (2015) ABSTRACT** Nearly all success is due to some mix of ability and luck. But some successes we attribute to the agent's ability, whereas others we attribute to luck. To better understand the criteria distinguishing credit from luck, we conducted a series of four studies on knowledge attributions. Knowledge is an achievement that involves reaching the truth. But many factors affecting the truth are beyond our control, and reaching the truth is often partly due to luck. Which sorts of luck are compatible with knowledge? We found that knowledge attributions are highly sensitive to lucky events that change the explanation for why a belief is true. By contrast, knowledge attributions are surprisingly insensitive to lucky events that threaten, but ultimately fail to change the explanation for why a belief is true. These results shed light on our concept of knowledge, help explain apparent inconsistencies in prior work on knowledge attributions, and constitute progress toward a general understanding of the relation between success and luck. **SOURCES** Turri, J., Buckwalter, W., & Blouw, P. (2015). Knowledge and luck. *Psychonomic Bulletin & Review, 22*(2), 378-390. Hall, B. F., Grahe, J. E., Brandt, M. J., Chartier, C. R., Legate, N., Wagge, J. R., … Lazarevic, L. B. (2020, May 31). Accelerated CREP -- Turri,Buckwalter,Blouw (2015). Retrieved from osf.io/n5b3w