Instructions: Complete the following questions. Enter answers and explanations in this document. Show calculations in an Excel file, using a separate worksheet (tab) for each question.
- What is the mean value for the following scores?
10 35 40 60 55 25 50
- What is the median for the following amounts?
$11.75 $12.75 $13.00 $10.75 $11.50 $10.50 $10.75
- Refer to the following data and answer the questions below.
9 10 3 8 2
8 3 5 7 4
7 4 6 6 7
8 9 7 1 2
- What is the mean?
- What is the mode?
- What is the median?
- Refer to the following situation and answer the questions below.
A researcher gathered data on months free of drug use for offenders released from prison. The data on seven subjects are as follows:
8 6 7 7 9 4 8
- What is the range?
- What is the variance?
- What is the standard deviation?
- If you have a lowest score of 21 and a range of 47, what will be your highest score? Show all the steps of the calculation.
- Approximately what percent of scores fall between the mean and –1 and –2 standard deviations under the normal curve? Please provide an explanation for your answer.
- What percent of all scores fall below a z score of +1? Show all the steps of the calculation.
- In a distribution with a mean of 100 and a standard deviation of 15, what is the probability that a score will be 115 or higher? Show all the steps of the calculation.
- What is the z score for a raw score of 85 where the group mean is 75 and the standard deviation is 5?
- A warden is interested in the effectiveness of two different violence reduction programs to reduce violent interactions in her prison. To test for differences, the warden randomizes two groups implementing one program to each group. The amount of violent interactions per inmate is presented below. Using α = .05, perform an independent sample t-test of significance. Then answer the questions below. Show all steps of the calculations.
|Program A||Program B|
(t = 2.7, p< .05)
- What is the null hypothesis?
- What is the research hypothesis?
- If t = 2.7, p< 0.05, how would you interpret this hypothesis test?