Question

1. For each of the following, determine the type of statistical hypothesis to which the statement best corresponds (hint: directional/one-tailed or non-directional/two-tailed hypotheses)
   1. Violent criminals have higher testosterone levels than non-violent criminals. (1pt)

2. Boys and girls differ in spatial ability. (1pt)

3. Children who view violent television programs are not different in their level of aggression from children who view nonviolent programs. (1pt)

2. Suppose that in the population of adults in the United States, the average number of hours spent per year riding a bicycle is 20 with a standard deviation of 2 and that it forms a normal distribution. I select a random sample of 36 adults from Ohio to see if their average amount of time riding a bike per year differs from the population in the U.S. The mean for the Ohio sample is 18. Use the 4-step hypothesis testing to answer the research question. Set the alpha level at .05.

Step 1 (1pt): H₀:

                      H_A:

**Is this a one-tailed or two-tailed test?

Step 2 - State the criterion for rejection

Step 3 – Compute and report the test statistic

Step 4 – Make a decision and report conclusion in proper format

**Remember when hand calculating, you will compare your Z_obt to Z_crit.

3. Calculate the effect size (Cohen’s d) for the above problem, and provide a written interpretation
4. Calculate the 95% confidence intervals and explain what they indicate 


Answer 1