Your police agency is interested in understanding whether there is a difference in education level among police officers in different specializations, such as Narcotics Investigations, Traffic Enforcement, and SWAT.
This type of information can help determine whether particular educational backgrounds are more likely to end up in particular units, which could be helpful for recruiting and diversity purposes.
One way to investigate this is through an analysis of variance (ANOVA). ANOVA is a type of analysis that helps determine whether there are differences on a continuous variable (such as years of education) among different categories or groups (such as police unit).
You have been tasked with conducting a study comparing the years of education completed between different officer specialization groups. Group1 is Narcotics Investigators, Group 2 is Traffic Enforcement Officers, and Group 3 is SWAT Officers.
This assignment has 3 steps.
Step 1: Review the 3 videos at this site.
Use the information from the videos at the link above and what you learned in your intellipath lessons to help conduct this analysis and answer the questions that follow.
Step 2: Follow the instructions below to conduct the ANOVA in Microsoft Excel. The data you will use is in the following table:
| Subject | Group 1 | Group 2 | Group 3 |
| 1 | 12 | 14 | 18 |
| 2 | 14 | 12 | 18 |
| 3 | 14 | 14 | 18 |
| 4 | 14 | 14 | 17 |
| 5 | 12 | 16 | 20 |
| 6 | 18 | 18 | 16 |
| 7 | 12 | 18 | 12 |
| 8 | 13 | 16 | 14 |
| 9 | 19 | 18 | 12 |
| 10 | 12 | 16 | 12 |
For reference: Group1 = Narcotics Investigators, Group 2 = Traffic Enforcement Officers, Group 3 = SWAT Officers; 12 = high school/GED, 14 = Associate’s, 16 = Bachelor’s, 18 = Master’s, and 20 = Doctorate
Steps for analysis in Excel:
- Cut and paste the data from the table above into Microsoft Excel.
- Click the Data tab and then the Data Analysis button to open the statistical analysis dialogue box.
- Click into the input range box, and then highlight all of the data (to include the headers) in the Group 1, Group 2, and Group 3 columns.
- Click the Labels in First Row box to ensure Excel does not try to analyze the column headers as data.
- Click the New Worksheet Ply button so that Excel spits the data output into a new worksheet.
- Click “OK” to run the analysis.
Step 2: Answer the following questions using the analysis results that you generated:
- What is the average years of education for Group 1 (Narcotics Investigators)?
- What is the Average years of education for Group 3 (SWAT Officers)?
- What is the p-value for your ANOVA model? Is the p-value greater than or less than 0.05?
- Do you reject or accept the null hypothesis that states, “There is no difference between the groups in years of education.”
- Why did you reject or accept the null hypothesis?
- Which group, on average, has the most years of education?
Please submit your assignment.
Reference
Khan Academy. (2017). Analysis of variance (ANOVA) [Video file]. Retrieved from https://www.khanacademy.org/math/statistics-probability/analysis-of-variance-anova-library