Statistics
posted by War Eagle on .
1. The Chisquare distribution, used in the Chisquare test of independence, varies in shape by degrees of freedom. What does the Chisquare distribution look like for 4 degrees of freedom.
A) Unimodal and symmetric.
B) Bimodal and symmetric.
C) Unimodal and skewed to the left.
D) Unimodal and skewed to the right.
2.The Chisquare distribution, used in the Chisquare test of independence, varies in shape by degrees of freedom. What does it mean when the Chisquare value is small and the pvalue is large?
A) As the Chisquare value gets small, the probability value gets large. In this case you fail to reject Ho and believe the events are independent.
B) As the Chisquare value gets small, the probability value gets large. In this case you fail to reject Ho and believe the events are not independent.
C) As the Chisquare value gets small, the probability value gets large. In this case you reject Ho and believe the events are not independent.
D) As the Chisquare value gets small, the probability value gets large. In this case you reject Ho and believe the events are independent.
3. The χ2test for independence is a useful tool for establishing a causal relationship between two factors.
A) True
B) False
1. B
2. D
3. A
Are my answers correct?

1. D
Chi Square distributions are positively skewed (skewed to the right). As the degrees of freedom increases, the Chi Square distribution will approach a normal symmetrical distribution. Smaller degrees of freedom will skew more to the right.
2. A
Ho: The variables are independent.
Ha: The variables are not independent.
(Large pvalues result in failing to reject Ho.)
3. B
The alternative hypothesis (Ha) suggests that the variables are related, but the relationship is not necessarily a causal one.