# How to Calculate the sum, mean, mode, median, standard deviation, range, skew, and kurtosis for a group.

Essay 3

A researcher has recorded the reaction times of 20 individuals on a memory assessment. The following table indicates the individual times:

2.2

4.7

7.3

4.1

9.5

15.2

4.3

9.5

2.7

3.1

9.2

2.9

8.2

7.6

3.5

2.5

9.3

4.8

8.5

8.1

In this essay, demonstrate your ability to organize data into meaningful sets, calculate basic descriptive statistics, interpret the results, and evaluate the effects of outliers and changes in the variables. You may use Excel, one of the many free online descriptive statistics calculators, or calculate the values by hand and/or with a calculator.

Next, separate the data into two groups of 10; one group will be the lower reaction times, and the second group will be the higher reaction times. Then, address the following points in your essay response:

•Calculate the sum, mean, mode, median, standard deviation, range, skew, and kurtosis for each group.

•How do the two groups differ?

• Are there any outliers in either data group?

•What effect does an outlier have on a sample?

Lastly, double each sample by repeating the same 10 data points in each group. You will have a total of 20 data points for each group. After completing this, address the following in your essay response:

•Calculate the following for the new data groups: sum, mean, mode, median, standard deviation, range, skew, and kurtosis.

•Did any of the values change?

•How does sample size affect those values?

Part B: Research Study Critique

In this second portion of the Final Exam, you will identify and critically evaluate a quantitative research article based on a social science topic. Your selected article must include a research question(s) and/or hypothesis(es) and utilize statistical analyses covered in the course. The article must be peer-reviewed and published within the last 10 years.

In the body of your critique, describe the statistical approaches used, the variables included, the hypothesis(es) proposed, and the interpretation of the results. In your conclusion, suggest other statistical approaches that could have been used and, if appropriate, suggest alternative interpretations of the results. This process will allow you to apply the concepts learned throughout the course in the interpretation of actual scientific research.

Your critique must include the following sections:

1.Introduction: This section will include a general introduction of the quantitative study from a peer-reviewed source published within the last 10 years. The research questions and/or hypothesis(es) as well as the purpose of the study should be clearly defined.

2.Methods: Describe and evaluate the procedures and methods of data collection, measures/instruments used, the participants and how they were selected, and the statistical techniques used.

3.Results: In this section describe and critique the results presented in the study.

4.Discussion: Discuss and evaluate the efficacy of the results presented in the study. Address, the strengths, weaknesses, and limitations of the study, and suggest future research directions. Include additional forms of statistical analyses as part of the suggestions for future research.