statistics hw
Nouf777
homework_assignment_3.docxHomework Assignment #3
Questions 1 - 3: Complete the following questions by hand. Show your work on separate sheets of paper. Make sure all paper has your name on it and is stapled together. If you do not show your work, you will not get credit for these questions.
X Y
4 5
6 3
3 2
9 8
7 6
5 6
2 3
1 9
3 3
2 1
1. With respect to variable X, calculate
the mean/average __________
the median __________
the standard deviation* __________
* remember that this is a SAMPLE of a larger population and you want to be able to draw INFERENCES from the sample to the larger population
2. On an attached sheet, draw a scatterplot that illustrates the relationship with X (on the horizontal axis) and Y (on the vertical axis)
3. What is the correlation (Pearson’s r) of X and Y? ____________
Questions 4 and 5: Use “Crime Data” located on Blackboard under the Assignments tab to answer the following questions. Descriptions of the variables can be found in the file “Crime Data Codebook”.
4. With respect to average sentence (in days), what is
the mean/average __________
the median __________
the standard deviation* __________
* remember that this is a SAMPLE of a larger population and you want to be able to draw INFERENCES from the sample to the larger population
5. What is the correlation (Pearson’s r) of crime rate and population density?
___________
