Exam 13: Simple Linear Regression Analysis

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 tire sales (in thousands of tires)and advertising expenditures (in thousands of dollars).Based on the data set with 6 observations,the simple linear regression model yielded the following results. = 24 = 124 = 42 = 338 = 196 Find the estimated slope.

An experiment was performed on a certain metal to determine if the strength is a function of heating time.Results based on 10 metal sheets are given below.Use the simple linear regression model. = 30 = 104 = 40 = 178 = 134 Find the estimated y-intercept.

In simple linear regression analysis,if the error terms exhibit a positive or negative autocorrelation over time,then the assumption of constant variance is violated.

Consider the following partial computer output from a simple linear regression analysis. Test H₀: $\beta$ ₁ $\le$ 0 vs.H_a: $\beta$ ₁ > 0.

Consider the following partial computer output from a simple linear regression analysis. Write the equation of the least squares line.

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 = 1 + 1X.The time is in minutes and the strength is measured in pounds per square inch. Provide a managerial interpretation of the Y-intercept.

An experiment was performed on a certain metal to determine if the strength is a function of heating time.Results based on 10 metal sheets are given below.Use the simple linear regression model. = 30 = 104 = 40 = 178 = 134 Calculate the correlation coefficient.

After plotting the data point s on a scatter diagram,we have observed an inverse relationship between the independent variable (X)and the dependent variable (Y).Therefore,we can expect both the sample _____ and the sample _____________ to be negative values.