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book Introductory Econometrics 4th Edition by Jeffrey Wooldridge cover

Introductory Econometrics 4th Edition by Jeffrey Wooldridge

النسخة 4الرقم المعياري الدولي: 978-0324660609
book Introductory Econometrics 4th Edition by Jeffrey Wooldridge cover

Introductory Econometrics 4th Edition by Jeffrey Wooldridge

النسخة 4الرقم المعياري الدولي: 978-0324660609
تمرين 7
With a single explanatory variable, the equation used to obtain the between estimator is With a single explanatory variable, the equation used to obtain the between estimator is    where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with   but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section). (i) Letting   be the between estimator, that is, the OLS estimator using the time aver¬ages, show that    where the probability limit is defined as N . [Hint: See equations] (ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim   = 1 + T ( xa 2x). (iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods  Equation
where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with With a single explanatory variable, the equation used to obtain the between estimator is    where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with   but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section). (i) Letting   be the between estimator, that is, the OLS estimator using the time aver¬ages, show that    where the probability limit is defined as N . [Hint: See equations] (ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim   = 1 + T ( xa 2x). (iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods  Equation    but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section).
(i) Letting With a single explanatory variable, the equation used to obtain the between estimator is    where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with   but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section). (i) Letting   be the between estimator, that is, the OLS estimator using the time aver¬ages, show that    where the probability limit is defined as N . [Hint: See equations] (ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim   = 1 + T ( xa 2x). (iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods  Equation    be the between estimator, that is, the OLS estimator using the time aver¬ages, show that With a single explanatory variable, the equation used to obtain the between estimator is    where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with   but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section). (i) Letting   be the between estimator, that is, the OLS estimator using the time aver¬ages, show that    where the probability limit is defined as N . [Hint: See equations] (ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim   = 1 + T ( xa 2x). (iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods  Equation
where the probability limit is defined as N . [Hint: See equations]
(ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim With a single explanatory variable, the equation used to obtain the between estimator is    where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with   but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section). (i) Letting   be the between estimator, that is, the OLS estimator using the time aver¬ages, show that    where the probability limit is defined as N . [Hint: See equations] (ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim   = 1 + T ( xa 2x). (iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods  Equation    = 1 + T ( xa 2x).
(iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods
Equation With a single explanatory variable, the equation used to obtain the between estimator is    where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with   but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section). (i) Letting   be the between estimator, that is, the OLS estimator using the time aver¬ages, show that    where the probability limit is defined as N . [Hint: See equations] (ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim   = 1 + T ( xa 2x). (iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods  Equation    With a single explanatory variable, the equation used to obtain the between estimator is    where the overbar represents the average over time. We can assume that E(ai) = 0 because we have included an intercept in the equation. Suppose that i. is uncorrelated with   but Cov(xit, ai) = xa for all t (and i because of random sampling in the cross section). (i) Letting   be the between estimator, that is, the OLS estimator using the time aver¬ages, show that    where the probability limit is defined as N . [Hint: See equations] (ii) Assume further that the xit, for all t = 1, 2,T, are uncorrelated with constant variance a2. Show that plim   = 1 + T ( xa 2x). (iii) If the explanatory variables are not very highly correlated across time, what does part (ii) suggest about whether the inconsistency in the between estimator is smaller when there are more time periods  Equation
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Introductory Econometrics 4th Edition by Jeffrey Wooldridge
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