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ECONOMETRICS I. CHAPTER 8 MULTIPLE REGRESSION ANALYSIS: THE PROBLEM OF INFERENCE. Textbook: Damodar N. Gujarati (2004) Basic Econometrics , 4th edition, The McGraw-Hill Companies. 8.1 THE NORMALITY ASSUMPTION ONCE AGAIN.
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ECONOMETRICS I CHAPTER 8 MULTIPLE REGRESSIONANALYSIS: THE PROBLEMOF INFERENCE • Textbook: Damodar N. Gujarati (2004) Basic Econometrics, 4th edition, The McGraw-Hill Companies
8.1 THE NORMALITY ASSUMPTION ONCE AGAIN • We continue to assume that the ui follow thenormal distribution with zero mean and constant variance σ2. • With normality assumption we findthat the OLS estimators of the partial regression coefficients are best linear unbiasedestimators (BLUE).
8.3 HYPOTHESIS TESTING IN MULTIPLE REGRESSION: GENERAL COMMENTS
8.4 HYPOTHESIS TESTING ABOUTINDIVIDUAL REGRESSION COEFFICIENTS
8.4 HYPOTHESIS TESTING ABOUTINDIVIDUAL REGRESSION COEFFICIENTS
8.4 HYPOTHESIS TESTING ABOUTINDIVIDUAL REGRESSION COEFFICIENTS
8.4 HYPOTHESIS TESTING ABOUTINDIVIDUAL REGRESSION COEFFICIENTS
8.4 HYPOTHESIS TESTING ABOUTINDIVIDUAL REGRESSION COEFFICIENTS
8.4 HYPOTHESIS TESTING ABOUTINDIVIDUAL REGRESSION COEFFICIENTS
8.5 TESTING THE OVERALL SIGNIFICANCEOF THE SAMPLE REGRESSION
The Analysis of Variance Approach to Testing the Overall Significance of an Observed Multiple Regression: The F Test
The Analysis of Variance Approach to Testing the Overall Significance of an Observed Multiple Regression: The F Test
The Analysis of Variance Approach to Testing the Overall Significance of an Observed Multiple Regression: The F Test
The Analysis of Variance Approach to Testing the Overall Significance of an Observed Multiple Regression: The F Test
Testing the Overall Significance of a Multiple Regression: The F Test
Testing the Overall Significance of a Multiple Regression: The F Test
An Important Relationship between R2 and F where use is made of the definition R2 = ESS/TSS. Equation on the left shows how F and R2 are related. These two vary directly. When R2 = 0, F is zero ipso facto. The larger the R2, the greater the F value. In the limit, when R2 = 1, F is infinite. Thus the F test, which is a measure of the overall significance of the estimated regression, is also a test of significance of R2. In other words, testing the null hypothesis (8.5.9) is equivalent to testing the null hypothesis that (the population) R2 is zero.
Testing the Overall Significance of a MultipleRegressionin Terms of R2
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable This F value is highly significant, as the computed p value is 0.0008.
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable This F value is highly significant,suggesting that addition of FLR to the model significantly increases ESSand hence the R2 value.Therefore, FLR should be added to the model. Again, note that if you square the tvalue of the FLR coefficient in the multiple regression (8.2.1), which is (−10.6293)2, you will obtain the F value of(8.5.17).
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
The “Incremental” or “Marginal” Contribution of an Explanatory Variable
8.7 RESTRICTED LEAST SQUARES: TESTING LINEAR EQUALITY RESTRICTIONS
8.7 RESTRICTED LEAST SQUARES: TESTING LINEAR EQUALITY RESTRICTIONS
8.7 RESTRICTED LEAST SQUARES: TESTING LINEAR EQUALITY RESTRICTIONS
8.7 RESTRICTED LEAST SQUARES: TESTING LINEAR EQUALITY RESTRICTIONS
8.7 RESTRICTED LEAST SQUARES: TESTING LINEAR EQUALITY RESTRICTIONS
8.7 RESTRICTED LEAST SQUARES: TESTING LINEAR EQUALITY RESTRICTIONS