4.3 Lab Report Instructions

4.3.1 R Script

Do the following in R:

  1. Import the data into R.
  2. Convert any categorical variables to factors with appropriate levels and labels.
  3. Use table() to produce a contingency table.
  4. Use chisq.test() to conduct a \(\chi^2\) test on the contingency table.
  5. Calculate the following effect sizes:
    • The probability of donating after watching (a) an honest pleader and (b) a dishonest pleader.
    • Absolute risk
      • The absolute risk is the difference between these two probabilities.
    • Relative risk
      • The relative risk is the ratio of the above probabilities.
    • Odds ratio
      • The ratio of the odds of donating given (a) an honest pleader and (b) a dishonest pleader
      • First, calculate the odds for each group; the odds of donating is the number of donaters divided by the number of non-donaters.
      • Then divide the two odds.

4.3.2 Results

Your results section should include the following:

  • The total number of participants.
  • The number of participants remaining after dropping participants who suspected that some pleaders may have been dishonest.
  • The proportion of participants who donated from each group.
  • The results of the \(\chi^2\) test with associated effect size.

4.3.3 Discussion

Answer each of the following questions using complete sentences.

  • Do the results of this study support the hypothesis? Include a plain-language description of the hypothesis in your responses.
  • This study was an extension of a prior study (Gunderson et al., 2021) which asked participants to indicate how much they would be willing to donate to the family of the pleader in the video they watched. How do the results of the current study compare to the findings of Gunderson et al. (2021)?
  • What is one potential implication of the primary finding of this study?


Gunderson, C. A., Baker, A., Pence, A. D., & ten Brinke, L. (2021). Interpersonal consequences of deceptive expressions of sadness. Personality and Social Psychology Bulletin. https://doi.org/10.1177/01461672211059700