Since people have been getting vaccinated against COVID-19 in the U.S., a stand-up paddling rental company in Santa Barbara wants to know whether in the month of June, renters (n = 100) were satisfied enough with their experience. Renters rated their satisfaction on a 7-point scale, and in June, this satisfaction level was, on average, 5.6, with a standard deviation of 0.5. Their goal satisfaction level is 6.0. This company hired us to see whether they met their goal or if the discrepancy between 5.6 and 6 is probably due to sampling error. (10 points)

Why would the company want to run a single sample t-test to test their hypothesis? Explain in the context of the question. (1 point)

If the researcher conducts a two-tailed test, what is the null hypothesis? (1 point)

Calculate the t-test statistic. Show your work. (3 points)

Using R, calculate the probability of a test statistic as extreme as yours in a null hypothesis world. Paste the code. Instructions for how to do this are in the lecture. (1 point)

Using an α = .05, would you reject or fail to reject the null hypothesis? Interpret what this means in the context of the question. (2 points)

Calculate the effect size. Interpret this effect size according to Cohen’s d guidelines. (2 points)

A researcher wants to know whether reading fiction versus non-fiction books boosts creativity. They hypothesize that there will be a difference in levels of creativity between individuals who read a novel versus a biography once a week for two months. They have one sample of college students (n1=38) read a novel per week for two months, and they have a second sample of college students (n2=35) read a biography per week for two months. The novel reading sample score an average of 7.8 (s1= 2.4) on a creativity scale that ranges from 1-10, and the biography reading sample score an average of 5.3 (s2= 2.1). (12 points)

Why would the researcher run an independent samples t-test to test their hypothesis? Explain in the context of the question. (1 point)

If the researcher conducts a two-tailed test, what is the null hypothesis? (1 point)

Calculate the t-test statistic. Show your work. (5 points)

Using R, calculate the probability of a test statistic as extreme as yours in a null hypothesis world. Paste the code. Instructions for how to do this are in the lecture. (1 point)

Using an α = .05, would you reject or fail to reject the null hypothesis? Interpret what this means in the context of the question. (2 points)

Calculate the effect size. Interpret this effect size according to Cohen’s d guidelines. (2 points)