Exam 13: Chi-Square Tests

Based on 25 time-ordered observations from a simple regression model,we have determined the Durbin-Watson statistic,d = 1.39.At α = .05,test to determine if there is any evidence of positive autocorrelation.State your conclusions.

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. Calculate the 95 percent confidence interval for the 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. Using the simple linear regression model,find the estimated y-intercept.

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

Regression Analysis A local grocery store wants to predict its daily sales in dollars.The manager believes that the amount of newspaper advertising significantly affects 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?

The least squares regression line minimizes the sum of the

Consider the following partial computer output from a simple linear regression analysis. What is 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. Determine the standard error.

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

Consider the following partial computer output from a simple linear regression analysis. Calculate the t statistic used to test H₀: β₁ = 0 versus H_a: β₁ ≠ 0 at α = .001.

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.

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.The simple linear regression equation is = 1 + 1X.The time is in minutes and the strength is measured in pounds per square inch.One of the 10 metal sheets was heated for 4 minutes and the resulting strength was 6 lb per square inch.Calculate the value of the residual for this observation.

The following results were obtained from a simple regression analysis.Ŷ = 37.2895 − 1.2024X r² = .6744 s_b = .2934 For each unit change in X (independent variable),what is the estimated change in Y (dependent variable)?

Complete the following partial ANOVA table from a simple linear regression analysis with a sample size of 16 observations.Find the F statistic to test the significance of the model.

Consider the following partial computer output from a simple linear regression analysis with a sample size of 16 observations.Find the t test to test the significance of the model.

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

The _____________ measures the strength of the linear relationship between the dependent variable and the independent variable.

The experimental region is the range of the previously observed values of the dependent variable.

The dependent variable is the variable that is being described,predicted,or controlled.

In a simple linear regression model,the intercept term is the mean value of y when x equals _____.