| Literature DB >> 34912255 |
Rens van de Schoot1,2, Sonja D Winter3, Elian Griffioen1, Stephan Grimmelikhuijsen4, Ingrid Arts1, Duco Veen2,4, Elizabeth M Grandfield1, Lars G Tummers5.
Abstract
The popularity and use of Bayesian methods have increased across many research domains. The current article demonstrates how some less familiar Bayesian methods can be used. Specifically, we applied expert elicitation, testing for prior-data conflicts, the Bayesian Truth Serum, and testing for replication effects via Bayes Factors in a series of four studies investigating the use of questionable research practices (QRPs). Scientifically fraudulent or unethical research practices have caused quite a stir in academia and beyond. Improving science starts with educating Ph.D. candidates: the scholars of tomorrow. In four studies concerning 765 Ph.D. candidates, we investigate whether Ph.D. candidates can differentiate between ethical and unethical or even fraudulent research practices. We probed the Ph.D.s' willingness to publish research from such practices and tested whether this is influenced by (un)ethical behavior pressure from supervisors or peers. Furthermore, 36 academic leaders (deans, vice-deans, and heads of research) were interviewed and asked to predict what Ph.D.s would answer for different vignettes. Our study shows, and replicates, that some Ph.D. candidates are willing to publish results deriving from even blatant fraudulent behavior-data fabrication. Additionally, some academic leaders underestimated this behavior, which is alarming. Academic leaders have to keep in mind that Ph.D. candidates can be under more pressure than they realize and might be susceptible to using QRPs. As an inspiring example and to encourage others to make their Bayesian work reproducible, we published data, annotated scripts, and detailed output on the Open Science Framework (OSF).Entities:
Keywords: Bayes Factor (BF); Bayes truth serum; Ph.D. students; expert elicitation; informative prior; questionable research practices; replication study
Year: 2021 PMID: 34912255 PMCID: PMC8667468 DOI: 10.3389/fpsyg.2021.621547
Source DB: PubMed Journal: Front Psychol ISSN: 1664-1078
Descriptive statistics for Study 1 (N = 440), Study 3 (N = 198), and Study 4 (N = 127).
| Variable | Study 1 | Study 3 | Study 4 | |
| Gender | Male | 128 (29.09%) | 48 (24.24%) | 80 (62.99%) |
| Female | 247 (56.14%) | 121 (61.11%) | 35 (27.56%) | |
| Prefer not to disclose | 12 (2.73%) | 8 (4.04%) | 2 (1.57%) | |
| Missing | 53 (12.05%) | 21 (10.61%) | 10 (7.87%) | |
| Age | 31.65 (7.84; 24/70) | 31.40 (6.15; 24/64) | 29.06 (4.79; 23/48) | |
| Employment type | Standard Ph.D. candidate | 296 (67.27%) | 150 (75.76%) | 45 (35.43%) |
| No Ph.D. candidate but Ph.D. scholarship | 17 (3.86%) | 10 (5.05%) | 56 (44.09%) | |
| External Ph.D. candidate | 15 (3.45%) | 10 (5.10%) | 7 (5.51%) | |
| Other | 53 (12.01%) | 20 (10.10%) | 10 (7.87%) | |
| Missing | 59 (13.41%) | 8 (4.04%) | 9 (7.09%) | |
| Data: Collecting and/or analyzing | I collect and analyze | 370 (84.09%) | 139 (70.20%) | 103 (81.10%) |
| I collect, someone else analyses | 20 (4.55%) | 14 (7.07%) | 4 (3.15%) | |
| I analyze existing data | 37 (8.41%) | 32 (16.16%) | 14 (11.02%) | |
| My research is mainly theoretical | 7 (1.59%) | 9 (4.55%) | 4 (3.15%) | |
| Missing | 6 (1.36%) | 4 (2.02%) | 2 (1.57%) | |
| Certainty career in academics | Scale 1–10 | 6.76 (2.27; 1/10) | 6.82 (2.32; 1/10) | 5.39 (2.56, 1/10) |
| Ambition career in academics | Scale 1–10 | 6.80 (2.20; 1/10) | 6.91 (2.14; 1/10) | 5.50 (2.49; 1/10) |
| Perceived publication pressure | Scale 1–6 | 4.64 (0.91; 1/6) | ||
| Is publication pressure present in the research field? | Scale 1–10 | 7.11 (1.87; 1/10) | 7.41 (1.77;1/10) |
Data are mean (SD; min/max) or frequency (%).
Results in percentages of the vignette studies Study 1 (N = 440), Study 3 (N = 198), and Study 4 (N = 127).
| Study 1 | Study 3 | Study 4 | |||||||
| “Is this fraud?” (% Yes) | “Yes, I would try to publish” | “Have you experienced a similar situation?” (% Yes) | “Is this fraud?” (% Yes) | “Yes, I would try to publish” | “Have you experienced a similar situation?” (% Yes) | “Is this fraud?” (% Yes) | “Yes, I would try to publish” | “Have you experienced a similar situation?” (% Yes) | |
| Scenario 1: Data fabrication | 96.6% | 5.9% | 3.2% | 92.4% | 9.6% | 5.5% | 92.9% | 13.4% | 5.5% |
| ( | ( | ( | ( | ( | ( | ( | ( | ( | |
| Scenario 2: Deleting outliers to get significant results | 56.4% | 12.3% | 12.9% | ||||||
| ( | ( | ( | |||||||
| Scenario 3: Salami slicing | 65.2% | 32.0% | 9.3% | 16.6% | 38.9% | 17.2% | 23.6% | 32.8% | 17.3% |
| ( | ( | ( | ( | ( | ( | ( | ( | ( | |
| Scenario 4: Gift authorship | 42.4% | 59.2% | 30.3% | 40.6% | 58.8% | 16.7% | |||
| ( | ( | ( | ( | ( | ( | ||||
| Scenario 5: Excluding information | 71.7% | 12.1% | 13.6% | 72.4% | 16.1% | 15.8% | |||
| ( | ( | ( | ( | ( | ( | ||||
FIGURE 1Example of a stickered distribution using (A) the trial roulette method and (B) the probability distribution obtained with the SHELF software (Oakley and O’Hagan, 2010).
FIGURE 2The parametric beta distributions based on the experts’ stickered distributions for Scenario 1 (A; n = 34), 2 (B; n = 35) and 3 (C; n = 33).
FIGURE 3(A) A histogram of predicted data is shown based on the prior derived from the expert (shown in B). The red lines indicate the credibility interval of the prior predictive distribution, and the blue line the observed percentage. The probability value appeared to be <0.001, showing there is a prior-data conflict. A table with results per expert can be found on the OSF.
FIGURE 4Results for the prior predictive check (A–C), the DAC (D–F), and for the combination of the two (G–I) for each scenario separately. The dotted line represents the cut-off values used. The green dots in (G–I), indicate identical conclusions for both measures, and the orange dots indicate numerical differences. It should be noted all of these are boundary cases, for example, a PPC of 0.049 (conflict) and a DAC score of 0.98 (no conflict).
FIGURE 5Bayesian truth serum Results of Study 3 (A) and Study 4 (B).
Results of the Bayesian test of replication where Original refers to Study 3 and Replication refers to Study 4.
| Question | Scenario | Study | Mean | SD |
| BF1 | BF2 | BF3 |
| Admission estimate | Salami | Original | 28.10 | 32.45 | 12.18 | 4.51E + 22 | ||
| Replication | 36.54 | 31.19 | 13.20 | 2.69E + 22 | 5.30E + 22 | 0.67 | ||
| Gift authorship | Original | 42.45 | 35.67 | 16.75 | 2.74E + 36 | |||
| Replication | 42.69 | 32.07 | 15.00 | 4.59E + 26 | 6.71E + 27 | 6.67 | ||
| Excluding results | Original | 21.54 | 29.81 | 10.16 | 4.99E + 16 | |||
| Replication | 22.93 | 26.81 | 9.64 | 6.94E + 13 | 6.79E + 14 | 7.10 | ||
| Prevalence estimate | Salami | Original | 23.07 | 27.69 | 11.72 | 1.91E + 21 | ||
| Replication | 33.31 | 30.39 | 12.35 | 2.45E + 20 | 7.87E + 20 | 1.38 | ||
| Gift authorship | Original | 40.48 | 34.78 | 16.38 | 2.11E + 35 | |||
| Replication | 42.19 | 29.96 | 15.87 | 4.63E + 28 | 3.12E + 29 | 2.16 | ||
| Excluding results | Original | 22.58 | 27.47 | 11.57 | 6.48E + 20 | |||
| Replication | 29.44 | 29.52 | 11.24 | 5.05E + 17 | 3.96E + 18 | 4.65 |
BF1 refers to the Bayes Factor testing whether the estimate is zero or not. BF2 refers to the Bayes Factor Test for Replication Success. BF3 refers to the Equality of Effect Size Bayes Factor.