Help me solve the following
1) When there is a significant difference in the population, but the research fails to find one ...this is what kind of error?
2) Assume that when victims are asked how well their needs were met by the criminal justice system on a scale of 1 (not met at all) to 5 (met completely), the average response is 3.24. In a study of 130 victims, Brewster (2001) found that the average response to how police officers met victims' needs was 2.90 (standard deviation = 1.44). Perform a hypothesis test to determine if police officers respond less well to victims' needs than the criminal justice system as a whole. Use a 0.05 level of statistical significance. What is the alternative hypothesis?
3) Assume that the international average homicide victimization rate is 2.92 (per 100,000). In a sample of 24 industrialized nations, LaFree and Drass (2002) found that the mean homicide victimization rate was 1.49 (per 100,000; standard deviation = 0.44). Perform a hypothesis test to determine if the mean homicide rate in industrialized nations is different than the international average. Use a 0.05 level of statistical significance.
What is the alternative hypothesis?
4) We know that, on average, most people drive about 10 miles a day. We think that people living in Phoenix have a different average than this. We talk to 250 people that live Phoenix, and find that their average number of miles they drive per day is 15, with a standard deviation of 3.7. Conduct a hypothesis test to see if people in Phoenix drive a different amount; use a significant level of 0.05.
What is the alternative hypothesis?