Exam 14: 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 are the limits of the 95 percent confidence interval for the population slope?

When there is positive autocorrelation,over time,negative error terms are followed by positive error terms and positive error terms are followed by negative error terms.

The slope of the simple linear regression equation represents the average change in the value of the dependent variable per unit change in the independent variable (X).

The point estimate of the variance in a regression model is:

What value of the Durbin-Watson statistic indicates that there is no autocorrelation present in time-ordered data?

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. Determine a 95 percent confidence interval estimate of the daily average store sales based on $3000 advertising expenditures.The distance value for this particular prediction is reported as .

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

An experiment was performed on a certain metal to determine if the strength is a function of heating time.The sample size consists of 10 metal sheets.Residuals are calculated for all 10 metal sheets and ordered from smallest to largest.Determine the normal point for the second largest residual (ninth residual in the ordered array).

If there is significant autocorrelation present in a data set,the ________________ assumption is violated.

In a simple linear regression analysis,the correlation coefficient (a)and the slope (b)___________ have the same sign.

The correlation coefficient is the ratio of explained variation to total variation.

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.

The simple coefficient of determination is the proportion of total variation explained by the regression line.

In a simple linear regression model,the slope term is the change in the mean value of y associated with _____________ in x.

The error term is the difference between an individual value of the dependent variable and the corresponding mean value of the dependent variable.

A data set with 7 observations yielded the following.Use the simple linear regression model.

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).Residuals are calculated for all of the randomly selected six months and ordered from smallest to largest.Determine the normal score for the third residual in the ordered array.

Any value of the error term in a regression model _____________ any other value of the error term.

The least squares regression line minimizes the sum of the:

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.