A researcher is interested in whether peoples accuracy at identify emotions is different when they have reduced sleep. The researcher is going to show participants faces of people expressing different emotions and the participants have to identify the emotion being expressed. The researcher knows from prior research that the accuracy scores on this task are normally distributed with an average score of = 82 and a standard deviation of = 15. The researcher recruits 50 participants who had no sleep the previous night and finds that their average accuracy score is M = 77. a. Conduct a hypothesis test using = .01 to test the researchers hypothesis that extremely tired people have different accuracy at identifying emotions. b. Calculate the effect size (Cohens d) for this effect. c. Identify 1 feature of this study that the researcher could change to increase the likelihood that they reject the null hypothesis..

1. A researcher is interested in whether peoples accuracy at identify emotions is different when they
have reduced sleep. The researcher is going to show participants faces of people expressing
different emotions and the participants have to identify the emotion being expressed. The
researcher knows from prior research that the accuracy scores on this task are normally
distributed with an average score of = 82 and a standard deviation of = 15. The researcher
recruits 50 participants who had no sleep the previous night and finds that their average accuracy
score is M = 77. a. Conduct a hypothesis test using = .01 to test the researchers hypothesis that
extremely tired people have different accuracy at identifying emotions. b. Calculate the effect
size (Cohens d) for this effect. c. Identify 1 feature of this study that the researcher could change
to increase the likelihood that they reject the null hypothesis.