Statistics HW
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StatHW.docxQuestion 1
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Suppose that we have the following data on two paired samples. Are differences statistically significant? What is your t-value?
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Question 2
What does a multiple linear regression analysis examine?
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The relationship between more than one dependent and only one independent variable |
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The relationship between one or more than one dependent and only one independent variable
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The relationship between one dependent and more than one independent variables
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The relationship between more than one independent variables. |
Question 3
What is the correlation for variables X and Y?
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X |
Y |
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23 |
4 |
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10 |
3 |
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16 |
5 |
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18 |
7 |
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14 |
6 |
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31 |
12 |
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19 |
6 |
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0.80 |
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0.79 |
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0.91 |
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0.5 |
Question 4
What does a multiple linear regression analysis examine?
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The relationship between more than one dependent and only one independent variable |
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The relationship between one or more than one dependent and only one independent variable
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The relationship between one dependent and more than one independent variables
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The relationship between more than one independent variables. |
Question 5
What is the fundamental difference between quantitative data and qualitative data?
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Quantitative data are comprised of numbers known in advance, whereas qualitative data do not contain numbers. |
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Qualitative data are harder to obtain than quantitative data. |
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Quantitative data contain variables for which the values are known in advance; however, this is not necessarily the case with qualitative data. |
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Qualitative data are comprised of information that must be coded by researchers, whereas this is not the case with quantitative data. |
Question 6
Which of the following criteria cannot be used to determine the number of factors in an EFA?
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Asking a group of researchers before the analysis |
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Eigenvalue rule |
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Scree test |
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Parallel analysis |
Question 7
If you estimate a regression model comprised of 3 nominal variables with 2, 3, and 4 categories, respectively, how many "categorical" variables should be included in your estimation equation?
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3 |
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5 |
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7 |
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6 |
Question 8
What are some tools that we can use to determine how many segments should be retained after conducting a cluster analysis?
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Little omega |
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The dendrogram |
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The variance ratio criterion (VRC) |
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All options provided are valid. |
Question 9
Use the results from the factor analysis (pfc) below to determine the percentage of variance explained by the factor solution given the analyst retains all factors with eigenvalues greater than one.
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50.29 |
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100 |
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86.73 |
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97.81 |
Question 10
Use the data below to solve for the effect of education (Educ) on wages (Wage) holding all else constant.
Wage Educ Exper
5.1 8 21
4.95 9 42
6.67 12 1
4 12 4
7.5 12 17
13.07 13 9
4.45 10 27
19.47 12 9
13.28 16 11
8.75 12 9
11.35 12 17
11.5 12 19
6.5 8 27
6.25 9 30
19.98 9 29
7.3 12 37
8 7 44
22.2 12 26
3.65 11 16
20.55 12 33
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The effect is statistically insignificant at the 10 percent level of significance. |
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0.91 |
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1.48 |
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0.95 |
Question 11
What makes the interpretation of conditional effects extra challenging in logistic regression?
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It is not possible to model interaction effects in logistic regression
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The results has to be raised by its natural logarithm
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The conditional effect is dependent on the values of all X-variables
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The maximum likelihood estimation makes the results unstable |
Question 12
Suppose you run the follow factor analysis (pcf). How many factors should be retained in the model.
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1 |
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2 |
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3 |
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4 |
Question 13
What does the least squares method do exactly?
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Minimizes the distance between the data points
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Finds the least problematic regression line
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Finds those (best) values of the intercept and slope that provide us with the smallest value of the residual sum of squares
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Finds those (best) values of the intercept and slope that provide us with the smallest value of the sum of residuals |
Question 14
How do we interpret a dummy variable coefficient?
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The difference between two means |
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the difference between two coefficients |
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The difference between two R-squared values |
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None of the provided options are valid |
Question 15
What is the main difference between primary and secondary data?
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Secondary data are data that have already been gathered. |
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Primary data are not stored in institutional databased; however, this is not the case with primary data. |
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Primary data are data that have already been gathered; whereas secondary data are gathered for a specific research project or task. |
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Secondary data are data that have already been gathered; whereas primary data are gathered for a specific research project or task. |
Question 16
What is the standard deviation of a population comprised of the following values: 23, 10, 16, 18, 14, 31, and 19?
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6.77 |
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6.99 |
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6.27 |
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7 |
Question 17
What is the most severe type of missing data problem?
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When data are missing completely at random. |
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If a data point is unrelated to the value of the variable under analysis, but depends on another variable. |
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When the probability that a data point is missing depends on the variable under analysis. |
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Missing data comprised of outliers do not pose a problem. |
Question 18
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Age |
Subscribe |
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20 |
0 |
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23 |
0 |
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24 |
0 |
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25 |
0 |
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25 |
1 |
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26 |
0 |
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26 |
0 |
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28 |
0 |
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28 |
0 |
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29 |
0 |
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30 |
0 |
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30 |
0 |
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30 |
0 |
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30 |
0 |
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30 |
0 |
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30 |
1 |
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32 |
0 |
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32 |
0 |
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33 |
0 |
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33 |
0 |
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34 |
0 |
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34 |
0 |
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34 |
1 |
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34 |
0 |
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34 |
0 |
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35 |
0 |
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35 |
0 |
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36 |
0 |
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36 |
1 |
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36 |
0 |
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37 |
0 |
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37 |
1 |
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37 |
1 |
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38 |
0 |
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39 |
0 |
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40 |
1 |
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45 |
0 |
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48 |
1 |
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50 |
0 |
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53 |
1 |
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55 |
1 |
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0.26 |
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.023 |
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0.128 |
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0.021 |
Question 19
What are some procedures that we can use to validate a cluster solution?
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We can assess the "stability" of a cluster solution. |
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We can assess the degree to which a cluster solution results in differentiated segments. |
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We can use observable variables to "profile" a cluster solution. |
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All are valid techniques that can be used to validate a cluster solution. |
Question 20
Why is the number of dummy variables to be entered into the regression model always equal to the number of groups (g) minus 1 (g-1)?
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To avoid model misspecification |
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To increase the R-squared value |
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To avoid the situation of perfect multicollinearity |
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The control for other variables in the model. |
Question 21
Given the data below, what is the Euclidean distance between points E and F (remember, you can use the hypotenuse of a right triangle formed by points E and F in two-dimensional space)?
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customer |
price |
loyalty |
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a |
3 |
7 |
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b |
6 |
7 |
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c |
5 |
6 |
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d |
3 |
5 |
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e |
6 |
5 |
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f |
4 |
3 |
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g |
1 |
2 |
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1.414 |
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3.606 |
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7.07 |
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2.828 |
Question 22
For a given level of statistical significance, increasing the sample size will do what to the power of a statistical test.
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decrease |
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the power of a statistical test will not change |
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increase |
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It depends on the predetermined level of statistical significance. |
Question 23
Suppose you run a factor analysis (pcf) to obtain the following variable loadings. Are the results sufficient? What should the analyst do next?
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Yes, interpret the factors |
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No, implement an oblique factor rotation |
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No, estimate a new model |
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Yes, solve for communality as 1 - uniqueness |
Question 24
What will a factor loading in an orthogonal solution represent?
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partial correlation |
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correlation |
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multiple correlation |
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Eigenvalue |
Question 25
What is the primary difference between a quasi-experiment and an experiment?
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Experiments are comprised of randomly generated samples. |
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It is not possible to perform between-group analyses with quasi-experimental data. |
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Experiments are rare in the social sciences. |
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When conducting an experiment, researchers randomly assign units of analysis to treatment and control groups. |
Question 26
The Logit models is estimated by way of?
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Ordinary least squares |
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Poisson distribution |
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Negative binomial distribution |
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Maximum likelihood estimation |
Question 27
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?
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Gen1 |
Gen2 |
Gen3 |
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55 |
45 |
50 |
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55 |
50 |
52 |
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49 |
45 |
43 |
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57 |
46 |
48 |
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55 |
42 |
47 |
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49 |
43 |
45 |
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48 |
42 |
44 |
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54 |
45 |
49 |
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54 |
47 |
51 |
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44 |
42 |
44 |
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No, 12 |
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No, 14 |
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No, 11.92 |
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Yes, 11.92 |
