Extra Credit Assignment
1. Zscore
Assume a normal distribution with a mean of 40 and a
standard deviation of 6 and answer the following questions.
a. Find the proportion of the area beyond
50 (i.e. above 50).
 Draw a normal curve and place the mean
and the score 50.

Shade the area beyond 50.

Translate the score 50 to a z score using the z formula.
 Find the proportion of the shaded
area.
b. Find the proportion of the area between
50 and the mean.
c. Find the proportion of the area below
the score of 50.
d.
Find the proportion of the area
below the score of 40.
e.
Find the proportion of the area between the scores of 50 and 30.
2. ChiSquare
and Lambda.
Political
ID Republican
= 1 Democrat
= 2 
Income Low
= 1 High
= 2 
1 
2 
1 
2 
2 
1 
2 
1 
1 
2 
2 
2 
2 
2 
2 
1 
2 
1 
1 
2 
1 
1 
2 
2 
1 
1 
1 
1 
a) Use the table above and carry out a chisquare test manually.
b)
Calculate lambda manually.
c) Replicate the results above using SPSS and circle the values for significance and lamda.
d) Using the SPSS chi square table, find out the confidence level using that this relationship is reaching.
3. Regression
analysis
a.
How
effective is this model? (Use adjusted R^{2} )
b. Provide a substantive interpretation of the slope coefficient for Union Density.
c.
Analyze
the relationship using the significance level.
Model Summary 

Model 
R 
R Square 
Adjusted R Square 
Std. Error of the Estimate 
1 
.524^{a} 
.274 
.252 
9.03807 
a.
Predictors: (Constant), PR system?, Union density 
Coefficients^{a} 

Model 
Unstandardized Coefficients 
Standardized Coefficients 
t 
Sig. 

B 
Std. Error 
Beta 

1 
(Constant) 
9.083 
2.175 

4.177 
.000 
Union
density 
.213 
.063 
.371 
3.407 
.001 

PR
system? 
6.164 
2.292 
.292 
2.689 
.009 

a.
Dependent Variable: Percent women in lower house of parliament, 2005 

4. First, analyze the relationship between support for gun controls and education level.
(You can use SPSS. Make sure to include the directional
hypothesis, null hypothesis, significance, strength, direction, and substantive
interpretation in your discussion. Highlight the relevant numbers.)
Second, add
the gender variable as a control variable and find out if the original
relationship remains the same.
ID 
Support
for Gun controls 
Education
Level 
Gender 
1 
1.00 
1.00 
2.00 
2 
1.00 
1.00 
2.00 
3 
1.00 
1.00 
1.00 
4 
1.00 
1.00 
2.00 
5 
1.00 
1.00 
1.00 
6 
2.00 
2.00 
1.00 
7 
1.00 
1.00 
1.00 
8 
1.00 
2.00 
1.00 
9 
2.00 
2.00 
2.00 
10 
2.00 
2.00 
2.00 