# Question

Much has been made of the concept of experimenter bias, which refers to the fact that for even the most conscientious experimenters there seems to be a tendency for the data to come out in the desired direction. Suppose we use students as experimenters. All the experimenters are told that participants will be given caffeine before the experiment, but half the experimenters are told that we expect caffeine to lead to good performance, and half are told that we expect it to lead to poor performance. The dependent variable is the number of simple arithmetic problems the participant can solve in two minutes. The obtained data are as follows:

What would you conclude from these results?

What would you conclude from these results?

## Answer to relevant Questions

Calculate the 95% confidence limits on m1 2 m2 for the data in Exercise 14.1. Brescoll and Uhlmann (2008) investigated the hypothesis that when an observer views a videotape of a male expressing anger as opposed to sadness, the male in the anger condition isaccorded higher status than the male in the ...What is the role of random assignment in the anorexia study? Let’s modify Exercise 15.12 to have sample means of 25 and 28, with a pooled standard deviation of 8 and sample sizes of 20 and 20. (a) What is the a priori power of this experiment? (b) Run the t test on the data. (c) ...Use G*Power or Piface to calculate the power of the comparison of Thematic Apperception T scores from the parents of schizophrenic and normal subjects in Exercise 14.8.Post your question

0