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Question 1

What does the slope of the regression line tell us?

Answer 1

how much the average value of y changes per one unit change in x

Question 2

Which choice is not an appropriate term for the x variable in a regression equation?

Answer 2

depdent variable

Question 3

What is the best way to determine if there is a statistically significant relationship between 2 quanitative variables?

Answer 3

conduct a test of the null hypothesis that the population slope is 0

Question 4

The R^2 value is reported by researcher to be 49%. Which of the following statements is correct?

Answer 4

The independent variable explaoins 49% of the variability in the response variable.

Question 5

What is a confidence interval?

Answer 5

A range of values that is likely to contain the true population parameter with a certain confidence (usually 95%)

Question 6

What is a prediction interval?

Answer 6

A range of values that tells us where we are likely to find the actual value of 𝑌 for a specific 𝑋

Question 7

What is the main distinction between a confidence interval and a prediciton interval?

Answer 7

confidence interval estimates the mean value of y at a particular value of x, while a prediction interval estimates the range of y values at one particular value of x

Question 8

At what value is the prediction interval the narrowest?

Answer 8

at the mean value of x because we likely have a lot of data points clustered near that value.

Question 9

What are the 4 residual assumptions that must be held for a valid linear regression model?

Answer 9

LINH
1. Linearity
2.Independent
3.Normality
4.Homoscedasticity