STATISTICS

1. What is the main difference between primary and secondary data?

		Secondary data are data that have already been gathered.
		Primary data are not stored in institutional databased; however, this is not the case with primary data.
		Primary data are data that have already been gathered; whereas secondary data are gathered for a specific research project or task.
		Secondary data are data that have already been gathered; whereas primary data are gathered for a specific research project or task.

2. What is the most severe type of missing data problem?

		When data are missing completely at random.
		If a data point is unrelated to the value of the variable under analysis, but depends on another variable.
		When the probability that a data point is missing depends on the variable under analysis.
		Missing data comprised of outliers do not pose a problem.

3. Suppose you estimate the following 3 regression models that relate overall customer satisfaction scaled 1 (worst) to 10 (best) to customer evaluations scaled 1 (worst) to 10 (best) in the areas of product quality (X6), e-commerce (X7), complaint resolution (X9), salesforce image (X12), and so on (knowing all variables names is not necessary to answer this question).  Based on the output below, which model is best? 

		1
		2
		3
		all of the above

4. What is the p-value of the correlation between X and Y?

X	Y
23	4
10	3
16	5
18	7
14	6
31	12
19	6
21	7
11	2
29	8

		.0505
		0.1015
		0.0111
		0.0035

5. Use the following sales data to determine whether mean sales varies from one generation to the next.  Are the differences statistically significant?  What is your calculated F-value?

Gen1	Gen2	Gen3
55	45	50
55	50	52
49	45	43
57	46	48
55	42	47
49	43	45
48	42	44
54	45	49
54	47	51
44	42	44

		No, 12
		No, 14
		No, 11.92
		Yes, 11.92

6. Perform a statistical test to determine whether age is higher for those who subscribes to a business service.  What is your p-value assuming that the sample variances are the same?

Age	Subscribe
20	0
23	0
24	0
25	0
25	1
26	0
26	0
28	0
28	0
29	0
30	0
30	0
30	0
30	0
30	0
30	1
32	0
32	0
33	0
33	0
34	0
34	0
34	1
34	0
34	0
35	0
35	0
36	0
36	1
36	0
37	0
37	1
37	1
38	0
39	0
40	1
45	0
48	1
50	0
53	1
55	1
		.0050
		.0036
		0.0551
		0.0150

7. What is the primary difference between a quasi-experiment and an experiment?

		Experiments are comprised of randomly generated samples.
		It is not possible to perform between-group analyses with quasi-experimental data.
		Experiments are rare in the social sciences.
		When conducting an experiment, researchers randomly assign units of analysis to treatment and control groups.

8. What is the fundamental difference between quantitative data and qualitative data?

		Quantitative data are comprised of numbers known in advance, whereas qualitative data do not contain numbers.
		Qualitative data are harder to obtain than quantitative data.
		Quantitative data contain variables for which the values are known in advance; however, this is not necessarily the case with qualitative data.
		Qualitative data are comprised of information that must be coded by researchers, whereas this is not the case with quantitative data.

9. What does the least squares method do exactly?

		Minimizes the distance between the data points
		Finds the least problematic regression line
		Finds those (best) values of the intercept and slope that provide us with the smallest value of the residual sum of squares
		Finds those (best) values of the intercept and slope that provide us with the smallest value of the sum of residuals

10. Suppose you estimate a regression model that relates overall customer satisfaction scaled 1 (worst) to 10 (best) to customer evaluations scaled 1 (worst) to 10 (best) in the areas of product quality (X6), e-commerce (X7), complaint resolution (X9), product line (X11), and salesforce image (X12).  What percentage of the variation in X19 can be explained by variation in X6, X7, X9, X11, and X12 adjusting for the number of variables included in the model?

		55.95
		79.08
		71.06
		77.97

11. For a given level of statistical significance, increasing the sample size will do what to the power of a statistical test.

		decrease
		the power of a statistical test will not change
		increase
		It depends on the predetermined level of statistical significance.

12. Perform a statistical test to determine whether there is a statistically significant difference in age by whether a person subscribes to a business service.  What is your p-value for a 2-tail test assuming that the sample variances are the same?

Age	Subscribe
20	0
23	0
24	0
25	0
25	1
26	0
26	0
28	0
28	0
29	0
30	0
30	0
30	0
30	0
30	0
30	1
32	0
32	0
33	0
33	0
34	0
34	0
34	1
34	0
34	0
35	0
35	0
36	0
36	1
36	0
37	0
37	1
37	1
38	0
39	0
40	1
45	0
48	1
50	0
53	1
55	1
		0.007
		.0233
		0.128
		0.015

13. What is the correlation for variables X and Y?

X	Y
23	4
10	3
16	5
18	7
14	6
31	12
19	6
21	7
11	2
29	8

		0.78
		0.82
		0.91
		0.5

14. Use the data below to estimate a regression model that relates overall customer satisfaction (X19) scaled 1 (worst) to 10 (best) to customer evaluations scaled 1 (worst) to 10 (best) in the areas of product quality (X6), e-commerce (X7), complaint resolution (X9), product line (X11), salesforce image (X12) and firm size measured as 1 for large firms, 0 for small firms.  What are your results?  Interpret the slope coefficients, the coefficient of determination, and the standard error of the regression.

X3	X6	X7	X9	X11	X12	X19
1	9	4	6	5	6	8
0	8	3	7	8	3	6
1	9	3	6	7	6	9
1	6	3	4	5	5	5
1	9	3	5	6	5	7
0	7	3	4	4	4	5
1	7	4	3	2	5	6
1	6	3	5	4	5	6
1	6	4	7	6	6	7
1	6	5	6	6	6	6
1	9	3	5	7	5	7
1	6	5	4	4	6	6
0	10	6	7	7	7	8
0	9	4	6	8	5	8
1	6	5	7	7	6	8
0	9	3	7	8	4	7
0	6	4	6	6	5	6
1	6	4	7	6	6	7
1	6	3	6	6	6	7
1	9	5	6	5	7	8
0	5	4	5	4	5	5
1	10	6	6	8	8	10
0	9	4	5	7	5	7
1	9	2	7	7	5	9
0	6	4	5	5	5	5
1	6	4	6	4	5	7
0	9	3	6	8	4	6
0	7	3	6	5	4	5
0	9	3	6	8	4	6
1	8	4	4	4	5	5
0	7	3	4	6	5	6
1	8	3	5	5	4	6
1	7	4	5	5	5	5
1	8	3	6	5	5	7
1	7	4	4	5	7	6
0	9	3	4	6	3	5
0	9	3	5	6	5	7
1	10	4	7	8	6	9
1	8	4	6	5	5	8
0	6	5	5	4	6	6
1	8	3	6	5	5	7
0	9	4	5	7	5	8
1	9	5	7	7	6	9
1	5	5	7	5	8	8
0	8	3	7	8	3	6
1	6	4	6	6	6	7
0	10	4	6	5	5	7
1	6	4	8	6	6	8
0	10	4	6	7	7	9
1	8	4	6	7	6	9

15. Suppose you estimate a regression model that relates overall customer satisfaction scaled 1 (worst) to 10 (best) to customer evaluations scaled 1 (worst) to 10 (best) in the areas of product quality (X6), e-commerce (X7), complaint resolution (X9), product line (X11), and salesforce image (X12).  Please interpret the output below.  Are any of the results counterintuitive?  

16. What does a multiple linear regression analysis examine?

		The relationship between more than one dependent and only one independent variable
		The relationship between one or more than one dependent and only one independent variable
		The relationship between one dependent and more than one independent variables
		The relationship between more than one independent variables.

17. Suppose you estimate a regression model that relates overall customer satisfaction scaled 1 (worst) to 10 (best) to customer evaluations scaled 1 (worst) to 10 (best) in the areas of product quality (X6), e-commerce (X7), complaint resolution (X9), product line (X11), and salesforce image (X12).  What is the standard error of the regression?

18. What happens to the probability of committing a Type II error if we decrease the level of statistical significance?

		decrease
		the power of a statistical test will not change
		increase
		It depends on the predetermined level of statistical significance.

19. Suppose that we have the following data on two paired samples.  Are differences statistically significant?  What is your t-value?  

T_1	T_2
92	100
102	104
80	86
96	96
92	94
90	90
84	88
102	98
98	102
86	88
		Yes, 2.25
		No, 3.25
		Yes, 3.25
		No, 1.25

20. What is the standard deviation of a population comprised of the following values: 23, 10, 16, 18, 14, 31, and 19?

		6.77
		6.99
		6.27
		7