Probability and randomness are foundational statistical concepts used not only throughout the sciences, but also in our daily lives to guide our behavior and make sense of the world. Their importance and widespread use may suggest that they are easy concepts to understand, yet that seems not to be the case. A classic article by Tversky and Kahneman (1971) on the “belief in the law of small numbers” revealed that professional psychologists tended to incorrectly perceive a small sample that is randomly drawn from a population as representative of that population. This finding has been hugely influential, inspiring myriad subsequent studies into error and bias when reasoning about probability. 

 

In the current study, Hong and Feldman (2023) propose a conceptual replication and extension of Tversky and Kahneman (1971). The original article was shockingly sparse on details regarding the method, sample, and findings, and, to our knowledge, has never been replicated. These facts are especially concerning given the foundational status that the article holds in the field. Hong and Feldman (2023) have developed a conceptual replication project, using the same approach and targeting the same claims from Tversky and Kahneman (1971), but modifying the wording of the stimuli for clarity and appropriateness for lay respondents. Although Tversky and Kahneman (1971) relied on professional psychologists as participants, many of their claims were not restricted to that population, but rather were generalized to all people—which is also how the findings have been subsequently applied. Thus, the change from professional to lay responders is entirely appropriate and the study will be diagnostic of the original claims.

 

Finally, Hong and Feldman (2023) extend the target study by manipulating the sample size indicated in the stimuli. Tversky and Kahneman (1971) relied on a single sample size in each scenario, leaving open the question as to how sample size might impact respondents’ reasoning. Accordingly, Hong and Feldman (2023) vary the sample size across the scenarios to determine whether participants answer differently as the sample size increases. 

 

The Stage 1 manuscript was evaluated over two rounds of in-depth review, the first round consisting of detailed comments from two reviewers and the second round consisting of a close read by the recommender. Based on detailed responses to the reviewers' comments, the recommender judged that the manuscript met the Stage 1 criteria and was therefore awarded in-principle acceptance (IPA).

 

URL to the preregistered Stage 1 protocol: https://osf.io/fzbq7
 
Level of bias control achieved: Level 6. No part of the data or evidence that will be used to answer the research question yet exists and no part will be generated until after IPA.
 
List of eligible PCI RR-friendly journals:
 

• Advances in Cognitive Psychology
• Experimental Psychology
• F1000Research
• Journal of Cognition
• Meta-Psychology
• Peer Community Journal
• PeerJ
• Royal Society Open Science
• Swiss Psychology Open

 

 

1. Hong, C. K., & Feldman, G. (2023). Revisiting the “Belief in the law of small numbers”: Conceptual replication and extensions Registered Report of problems reviewed in Tversky and Kahneman (1971). In principle acceptance of Version 3 by Peer Community in Registered Reports. https://osf.io/fzbq7

 

2. Tversky, A., & Kahneman, D. (1971). Belief in the law of small numbers. Psychological Bulletin, 76(2), 105–110. https://doi.org/10.1037/h0031322   

Decisions to give to charities are affected by numerous external and internal factors. Understanding the elements that influence donation decisions is of first-order importance for science and society. On the scientific side, understanding the determinants of charity giving contributes to the knowledge of altruistic behaviors in the presence of collective problems such as poverty, climate change, or animal welfare. On the social side, pointing out which factors affect donations can help increase pro-social behaviors and might facilitate collective actions in the case of public goods. 

 

Previous work identified multiple mechanisms affecting altruistic donations to charities (Bekkers and Weeping, 2011). Importantly, Baron and Szymanska (2011) collected empirical evidence suggesting that people prefer (i) their donations to be directly used for projects rather than organizational costs, (ii) when charities have low past costs, (iii) to diversity their donations into several NGOs, (iv) to favor charities that deal with close peers like nationals, and (v) to give voluntarily rather than through taxes. 

 

In the current study, Chan and Feldman seek to replicate the results of Baron and Szymanska (2011). They propose a close replication of the original study using a large sample of online participants (1,400 participants). In addition to the five mechanisms identified by the original study, they will further explore whether public donation increases contributions and whether individuals are more likely to donate when the charities’ overhead costs are paid for by other donors. 

 

The Stage 1 manuscript was evaluated over two rounds of in-depth review. Based on detailed responses to the reviewers' comments, the recommender judged that the manuscript met the Stage 1 criteria and therefore awarded in-principle acceptance (IPA).

 

URL to the preregistered Stage 1 protocol: https://osf.io/gmswz
 
Level of bias control achieved: Level 6. No part of the data or evidence that will be used to answer the research question yet exists and no part will be generated until after IPA.
 
List of eligible PCI RR-friendly journals:

 

 

 

1. Baron, J. & Szymanska, E. (2011). Heuristics and Biases in Charity. In D. M. Oppenheimer & C. Y. Olivola (Eds.), The Science of Giving: Experimental Approaches to the Study of Charity (pp. 215–235). Psychology Press. 

 

2. Bekkers, R. & Wiepking, P. (2011). A Literature Review of Empirical Studies of Philanthropy. Nonprofit and Voluntary Sector Quarterly, 40, 924–973.

 

3. Chan, M. & Feldman, G. (2023). Factors impacting effective altruism: Revisiting heuristics and biases in charity in a replication and extensions Registered Report of Baron and Szymanska (2011), in principle acceptance of Version 3 by Peer Community in Registered Reports. https://osf.io/gmswz

Human meat consumption is associated with a variety of risks to health, animal welfare, sustainability, and the environment (including greenhouse gas emissions and loss of biodiversity), prompting a growing research effort to develop psychological interventions to reduce it and encourage alternative diets. At the same time, although meat consumption remains the majority choice in the UK, its prevalence is declining, with the proportion of vegetarians and vegans increasing substantially over the last two decades.

 

One potential tool to accelerate behaviour change is to expose people to “dynamic norm” messaging, which, rather than providing static descriptive information about the prevalence of a desired behaviour, emphasises how the desired behaviour is changing over time so that people can begin to conform to the emerging trend. Although promising in theory, previous research offers mixed evidence on the effectiveness of dynamic norms in encouraging a reduction in meat consumption, with some studies suggesting benefits and others showing no effect or even counterproductive effects. The methodological rigour of some studies is also in question.

 

In the present study, Aldoh et al. (2023) investigated the effectiveness of dynamic norm information (compared to static norms) on several indicators of meat consumption, including interest, attitudes, and intentions toward reducing meat consumption, as well as self-reported meat consumption itself. Using an online sample of ~1500 participants, the authors also tested the role of visual cues (including data trend graphics) in causing any effects and explored the potential longevity of the intervention over a period of 7 days. Results revealed moderate evidence for no net effect of dynamic (compared to static) norm information on meat consumption outcomes, nor any positive change over the 7-day period. However, the addition of visual cues enhanced the effect of dynamic norm messages, suggesting potential avenues for increasing the potency of future messaging interventions.

 

The Stage 2 manuscript was evaluated over one round of in-depth review, following which the recommender judged that the manuscript met the Stage 2 criteria and awarded a positive recommendation.

 

 

Level of bias control achieved: Level 6. No part of the data or evidence that was used to answer the research question was generated until after IPA. 

 

 

  

1. Aldoh, A., Sparks, P. & Harris, P. R. (2023). Communicating dynamic norm information [Stage 2]. Acceptance of Version 1 by Peer Community in Registered Reports. https://doi.org/10.31234/osf.io/tac3j

In a time when open research practices are becoming more widely used to combat questionable research practices (QRPs) in academia, this Registered Report by Pownall and colleagues (2023) empirically investigated the practice of preregistering study plans, which allows us to better understand to what degree such practices increase awareness of QRPs and whether experience with preregistration helps reduce engagement in QRPs. This investigation is timely because results from these kinds of studies are only recently becoming available and the conclusions are providing evidence that open research practices can improve research quality and reliability (e.g., Soderberg et al. 2021, Chambers & Tzavella 2022). The authors crucially focused on the effect of preregistering the undergraduate senior thesis (of psychology students in the UK), which is a key stage in the development of an academic.

 

Pownall and colleagues found that preregistration did not affect attitudes toward QRPs, but it did improve student understanding of open research practices. Using exploratory analyses, they additionally found that those who preregistered were those students who reported that they had more opportunity, motivation, and greater capability. This shows how important it is to incorporate the teaching of open research practices such that students can increase their capability, motivation, and opportunity to pursue such practices, whether it is preregistration or other practices that are better known to reduce QRPs (such as registered reports; Krypotos et al. 2022). 

 

After four rounds of review and revisions, the recommender judged that the manuscript met the Stage 2 criteria and awarded a positive recommendation.

 

URL to the preregistered Stage 1 protocol: https://osf.io/9hjbw

 

Level of bias control achieved: Level 6. No part of the data or evidence that was used to answer the research question was generated until after IPA.

 

 

• Advances in Cognitive Psychology
• Advances in Methods and Practices in Psychological Science
• Cambridge Educational Research e-Journal
• Collabra: Psychology
• Experimental Psychology
• F1000Research
• Meta-Psychology
• Peer Community Journal
• PeerJ
• Royal Society Open Science
• Studia Psychologica
• Swiss Psychology Open

 

 

1. Chambers C. D. & Tzavella, L. (2022). The past, present, and future of Registered Reports. Nature Human Behaviour, 6, 29-42. https://doi.org/10.1038/s41562-021-01193-7

 

2. Krypotos, A. M., Mertens, G., Klugkist, I., & Engelhard, I. M. (2022). Preregistration: Definition, advantages, disadvantages, and how it can help against questionable research practices. In Avoiding Questionable Research Practices in Applied Psychology (pp. 343-357). Cham: Springer International Publishing.

 

3. Pownall, M., Pennington, C. R., Norris, E., Juanchich, M., Smaile, D., Russell, S., Gooch, D., Rhys Evans, T., Persson, S., Mak, M. H. C., Tzavella, L., Monk, R., Gough, T., Benwell, C. S. Y., Elsherif, M., Farran, E., Gallagher-Mitchell, T., Kendrick, L. T., Bahnmueller, J., Nordmann, E., Zaneva, M., Gilligan-Lee, K., Bazhydai, M., Jones, A., Sedgmond, J., Holzleitner, I., Reynolds, J., Moss, J., Farrelly, D., Parker, A. J. & Clark, K. (2023). Evaluating the pedagogical effectiveness of study preregistration in the undergraduate dissertation [Stage 2 Registered Report], acceptance of Version 4 by Peer Community in Registered Reports. https://psyarxiv.com/xg2ah

 

4. Soderberg C. K., Errington T. M., Schiavone S. R., Bottesini J., Thorn F. S., Vazire S., Esterling K. M. & Nosek B. A. (2021) Initial evidence of research quality of registered reports compared with the standard publishing model. Nature Human Behaviour, 5, 990–997. https://doi.org/10.1038/s41562-021-01142-4

The Virtual Maze Task (VMT) is a digital desktop 2D spatial learning task that has been used for research into the effect of sleep and dreaming on memory consolidation (e.g. Wamsley et al, 2010). One limitation of this task has been low rates of reported dream incorporation. Eudave and colleagues (2023) have created an immersive virtual reality (iVR) version of the VMT, which they believe might be more likely to be incorporated into dreams. As an initial step in validating this task for research, they propose a within-subjects study to compare three measures of spatial learning between the 2D desktop and iVR versions. Based on a review of relevant literature, the prediction is that performance will be similar between the two task versions. The planned sample size (n = 62) is sufficient for a .9 power test of equivalence within effect size bounds of d = -.47 to .47. Additional independent variables (gender, perspective-taking ability) and dependent measures (self-reported cybersickness and sense of presence) will be recorded for exploratory analyses.

 

The study plan was refined across four rounds of review, with input from two external reviewers and the recommender, after which it was judged to satisfy the Stage 1 criteria for in-principle acceptance (IPA).†

 

URL to the preregistered Stage 1 protocol: https://osf.io/wba2v
 
Level of bias control achieved: Level 6. No part of the data or evidence that will be used to answer the research question yet exists and no part will be generated until after IPA.
 
List of eligible PCI RR-friendly journals:
 

 

 

Eudave, L., Martínez, M., Valencia, M., & Roth D. (2023). Evaluation of spatial learning and wayfinding in a complex maze using immersive virtual reality. A registered report. In principle acceptance of Version 5 by Peer Community in Registered Reports.

 

Wamsley, E. J., Tucker, M., Payne, J. D., Benavides, J. A., & Stickgold, R. (2010). Dreaming of a learning task is associated with enhanced sleep-dependent memory consolidation. Current Biology, 20, 850–855. https://doi.org/10.1016/j.cub.2010.03.027