问题


There is a single choice question about econometrics. Answer the question by replying A, B, C or D.
Question: Consider the OLS estimator for the standard error of the slope coefficient. Which of the following statement(s) is (are) true?

(i) The standard error will be positively related to the residual variance

(ii) The standard error will be negatively related to the dispersion of the observations on the explanatory variable about their mean value

(iii) The standard error will be negatively related to the sample size

(iv) The standard error gives a measure of the precision of the coefficient estimate.
A. (ii) and (iv) only
B. (i) and (iii) only
C. (i), (ii), and (iii) only
D. (i), (ii), (iii), and (iv)
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0

D. (i), (ii), (iii), and (iv)

Explanation:

(i) The standard error of the slope coefficient is positively related to the residual variance, as a higher residual variance indicates more variability in the data, which increases the uncertainty of the coefficient estimate.

(ii) The standard error of the slope coefficient is negatively related to the dispersion of the observations on the explanatory variable about their mean value. This is because a larger dispersion of the explanatory variable leads to a more precise estimate of the slope coefficient.

(iii) The standard error of the slope coefficient is negatively related to the sample size. As the sample size increases, the standard error decreases, indicating a more precise estimate of the slope coefficient.

(iv) The standard error gives a measure of the precision of the coefficient estimate. A smaller standard error indicates a more precise estimate, while a larger standard error indicates a less precise estimate.

Therefore, all four statements are true, and the correct answer is D.
D
deepseekr1

The OLS estimator's standard error for the slope coefficient is derived from the formula:
\[ \text{SE}(\hat{\beta}_1) = \frac{\sigma}{\sqrt{n \cdot \text{Var}(X)}} \]
where \(\sigma^2\) is the residual variance, \(n\) is the sample size, and \(\text{Var}(X)\) is the variance of the explanatory variable.

- **(i)**: The standard error is **positively related** to the residual variance (\(\sigma^2\)). An increase in \(\sigma^2\) directly increases the numerator, leading to a larger SE. **True**.
- **(ii)**: The standard error is **negatively related** to the dispersion of \(X\) (\(\text{Var}(X)\)). A higher \(\text{Var}(X)\) increases the denominator, reducing the SE. **True**.
- **(iii)**: The standard error is **negatively related** to the sample size (\(n\)). Larger \(n\) increases the denominator (\(\sqrt{n}\)), decreasing the SE. **True**.
- **(iv)**: The standard error measures the **precision** of the coefficient estimate. A smaller SE indicates higher precision, and the SE itself quantifies uncertainty. **True**.

All four statements are correct. **Answer: D**
D
gpto1 D D
GPT-4o D. (i), (ii), (iii), and (iv) D
llama3.1-70B-Instruct

D
D
llama3.1-405B-Instruct

D. (i), (ii), (iii), and (iv)
D
DeepSeek-Coder-V2 B D
Qwen2-72B-Instruct D. (i), (ii), (iii), and (iv) D
baichuan4 D. (i), (ii), (iii), and (iv) D
doubao D

(i) is true as a larger residual variance leads to a larger standard error. (ii) is true as a greater dispersion of the explanatory variable reduces the standard error. (iii) is true as a larger sample size typically leads to a smaller standard error. (iv) is also true as the standard error indeed measures the precision of the coefficient estimate. So all statements are correct.
D
minimax D. (i), (ii), (iii), and (iv) D
kimi D. (i), (ii), (iii), and (iv)

Explanation:
(i) The standard error of the slope coefficient is indeed positively related to the residual variance (the variance of the errors). If the residuals are more variable, the estimates of the coefficients are less precise.

(ii) The standard error is negatively related to the dispersion of the observations on the explanatory variable about their mean value. If the explanatory variable is more dispersed (i.e., has a greater range or variance), the estimates of the coefficients are more precise because there is more information about the relationship between the variables.

(iii) The standard error is negatively related to the sample size. As the sample size increases, the estimates of the coefficients become more precise because there is more information available.

(iv) The standard error does give a measure of the precision of the coefficient estimate. It is a measure of the variability of the estimate and reflects the uncertainty associated with the estimate.
D
wenxinyiyan A. (ii) and (iv) only

Explanation:

(i) The standard error of the slope coefficient in OLS (Ordinary Least Squares) estimation is indeed related to the residual variance, but it is not just positively related. It also depends on other factors such as the variation in the explanatory variable. So, this statement is not complete and can be misleading.

(ii) The standard error of the slope coefficient is negatively related to the dispersion of the observations on the explanatory variable about their mean value. This is because a greater dispersion (or variance) in the explanatory variable provides more information for estimating the slope, resulting in a more precise estimate with a smaller standard error.

(iii) The standard error of the slope coefficient is not negatively related to the sample size. In fact, as the sample size increases, the standard error typically decreases because we have more information to estimate the coefficient. So, this statement is incorrect.

(iv) The standard error of the slope coefficient does give a measure of the precision of the coefficient estimate. It indicates the amount of variability or uncertainty in the estimate. A smaller standard error suggests a more precise estimate.
D
zhipu D. (i), (ii), (iii), and (iv)

Explanation:
(i) The standard error of the slope coefficient is positively related to the residual variance. As the residual variance increases, the standard error also increases, indicating more uncertainty in the slope estimate.

(ii) The standard error will be negatively related to the dispersion of the observations on the explanatory variable about their mean value. A larger dispersion (i.e., a larger variance of the explanatory variable) leads to a smaller standard error, as it provides more information to estimate the slope coefficient.

(iii) The standard error will be negatively related to the sample size. As the sample size increases, the standard error decreases, reflecting greater precision in the estimate of the slope coefficient.

(iv) The standard error gives a measure of the precision of the coefficient estimate. A smaller standard error indicates a more precise estimate.

Therefore, all the statements (i), (ii), (iii), and (iv) are true, making the correct answer D.
D
gpto1 D D