USA: +1(669)289-8683 
Sign in
Stat Questions
2. true or false: the y intercept measures the strength of the linear relationship between two numerical variables.
4. we intercept the slope of the regression line as the estimated change in y per ________ increase in x
6. values of r close to -1 indicate what type of relationship between the two variables?
Use the following information for questions 8 through 14. The federal bureau of investigation publishes crime statistics, including those in the following table, which shows the percentage of violent crime committed per month nationwide for the years 2002 and 2004.
Month———2002——–2004
January——–7.9———–7.8
February—– 6.8———–7.0
March———7.9———–8.3
April———–8.1———–8.2
May————8.7———-9.0
June———–8.8———-8.6
July————9.3———–9.2
August——–9.3———-9.0
September—9.2———8.5
October——-8.6———8.6
November—-7.7———7.8
December—7.7———-7.9
8. Based on your scatterplot, would you characterize the linear relationship, if any, as positive or negative?
10. Calculate the three sums of squares: SSR, SST, and SSE
12. Calculate r2. comment on how useful the 2002 percentages are in predicting the 2004 percentages.
14. find the prediction error for the following percentages: A) 7.9 B) 9.3 C) 8.1
2. true or false: when β1 = 0, there is no relationship between the predictor variable and the response variable.
4. two other terms for the fitted values of a regression are the a)______ and the b)________values
6. a predictor variable used to recode a binomial categorical variable in regression, and taking values 0 or 1, is called a ______ variable.
8. What other form of inference is the 100(1-α)% confidence interval for β1 equivalent to?
10. The university medical unit is collecting data on the heights and weights of the male students on campus. A random sample of ten male students showed the following heights (in inches) and weights (in pounds). Test for a linear relationship between height and weight using level of significance α = 0.01
Student———–height—————-weight
1—————–66——————-150
2—————–68——————-145
3—————–69——————-160
4—————–70——————-165
5—————–70——————-165
6—————–71——————–180
7—————–72——————-175
8—————–72——————-180
9—————–73——————-195
10—————-75——————-210
12. using the data in problem 10, do the following.
a) find the point estimate of the height of a man 70 inches tall
b) calculate and interpret a 95% confidence interval for the mean height of all men 70 inches tall.
c) compute and interpret a 95% prediction interval for a randmomly chosen man 70 inches tall
2. true or false: in a test for independence, the degrees of freedom equals k-1
4. the conditions for performing a goodness of fit test are that none of the expected frequencies is less than _____, and, at most, 20% of the expected frequencies are less than _____.
