A totally fictitious researcher wants to test whether there is a significant relationship between number of shih tzus owned and happiness. After analyzing the data on a sample of 50, she determines that r = 0.34. What is her calculated t score?

A researcher wants to know if there is a significant relationship between job experience and job stress. From a sample of 10 correctional officers, she collects data on the number of years of work experience and job stress measured on a scaled ranging from 0 to 10. 

Below is a diagram representing an OLS regression with two predictors, X1 and X2.  Which of the following represents the proportion of variance in Y NOT explained by X1 and X2?

Which variable do we have the highest level of confidence in?

Is there a sex difference in running red lights? A researcher recorded traffic violations and driver sex in the table below. What are the degrees of freedom? 

Which condition must be satisfied for chi-square to be valid?

Below is a diagram representing an OLS regression with two predictors, X1 and X2.  What does A + D represent?

Match the appropriate term with its definition. 

The biological species concept cannot be applied to ______.

Phylogenetic trees are useful because_______.