Exam 14: Simple Linear Regression Analysis

Based on 30 time-ordered observations from a simple regression,we have determined the Durbin-Watson statistic,d = 2.71.At α = .05,test to determine if there is any evidence of negative autocorrelation.State your conclusions.

Consider the following partial computer output from a simple linear regression analysis.

Regression Analysis The local grocery store wants to predict its daily sales in dollars.The manager believes that the amount of newspaper advertising significantly affects the store's sales.He randomly selects 7 days of data consisting of daily grocery store sales (in thousands of dollars)and advertising expenditures (in thousands of dollars).The Excel/MegaStat output given above summarizes the results of the regression model. What is the estimated simple linear regression equation?

A local tire dealer wants to predict the number of tires sold each month.He believes that the number of tires sold is a linear function of the amount of money invested in advertising.He randomly selects 6 months of data consisting of monthly tire sales (in thousands of tires)and monthly advertising expenditures (in thousands of dollars).The simple linear regression equation is ŷ = 3 + 1x,and the sample correlation coefficient (r²)= .6364.Test to determine if there is a significant correlation between the monthly tire sales and monthly advertising expenditures.Use H₀: ρ = 0 vs.H_A: ρ ≠ 0 at α = .05.

An experiment was performed on a certain metal to determine if the strength is a function of heating time.The simple linear regression equation is

In simple regression analysis,the standard error is ___________ greater than the standard deviation of y values.

A significant positive correlation between X and Y implies that changes in X cause Y to change.