问题


There is a single choice question about high school statistics. Answer the question by replying A, B, C or D.
Question: For the regression line, which of the following statements about residuals is true?
A. Influential scores have large residuals.
B. If the linear model is good, the number of positive residuals will be the same as the number of negative residuals.
C. The mean of the residuals is always zero.
D. If the correlation is 0, there will be a distinct pattern in the residual plot.
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0

C. The mean of the residuals is always zero.

Explanation: In a regression analysis, the residuals are the differences between the observed values and the predicted values based on the regression line. One of the properties of residuals is that their mean is always zero. This is because the regression line is calculated to minimize the sum of the squared residuals, and as a result, the positive and negative residuals balance each other out, leading to a mean of zero.

Influential scores may or may not have large residuals (A), depending on their position relative to the regression line. While it's true that a good linear model will have a mix of positive and negative residuals, it's not a requirement that the number of positive residuals will be exactly the same as the number of negative residuals (B). If the correlation is 0, the residual plot will not show a distinct pattern (D), as a correlation of 0 indicates no linear relationship between the variables.
C
deepseekr1

The correct answer is **C**.

**Explanation:**
- **A** is incorrect because influential points may not have large residuals; they can pull the regression line closer, reducing their residuals.
- **B** is false since a good linear model ensures the *sum* (not count) of residuals is zero, but the number of positive and negative residuals need not be equal.
- **C** is true because the ordinary least squares (OLS) regression method ensures the mean of residuals is always zero.
- **D** is incorrect because a zero correlation implies no linear relationship, resulting in a residual plot with no distinct pattern (randomly scattered residuals).

Answer: C
C
gpto1 C C
GPT-4o C. The mean of the residuals is always zero. C
llama3.1-70B-Instruct

C
C
llama3.1-405B-Instruct

C. The mean of the residuals is always zero.

Explanation: In a regression analysis, the residuals are the differences between the observed values and the predicted values based on the regression line. One of the properties of residuals is that their mean is always zero. This is because the regression line is calculated to minimize the sum of the squared residuals, and as a result, the positive and negative residuals balance each other out, leading to a mean of zero.

Influential scores may or may not have large residuals (A), depending on their position relative to the regression line. While it's often true that the number of positive residuals is roughly equal to the number of negative residuals if the linear model is good (B), this isn't a strict rule and can vary depending on the data. If the correlation is 0, the residual plot would not show a distinct pattern (D), as a correlation of 0 indicates no linear relationship between the variables, leading to a random scatter of residuals.
C
DeepSeek-Coder-V2 C. The mean of the residuals is always zero. C
Qwen2-72B-Instruct C. The mean of the residuals is always zero. C
baichuan4 C C
doubao C

In a good regression model, the sum of the residuals is zero, and thus the mean of the residuals is always zero. Option A is not always true as influential scores may or may not have large residuals. Option B is not necessarily true. Option D is incorrect as if the correlation is 0, there is no pattern in the residual plot.
C
minimax C. The mean of the residuals is always zero. C
kimi C. The mean of the residuals is always zero.

In the context of regression analysis, residuals are the differences between the observed values and the values predicted by the regression model. The regression line is calculated in such a way that the sum of the residuals is minimized, and as a result, the mean of the residuals is zero. This is a fundamental property of the least squares regression line.
C
wenxinyiyan C

Explanation:
A. Influential scores do not necessarily have large residuals. A score may be influential in determining the regression line, but its residual (the vertical distance from the data point to the regression line) may not be large.

B. If the linear model is good, it does not necessarily mean that the number of positive residuals will be the same as the number of negative residuals. A good model means that the residuals are randomly distributed around zero, but there could be more positive or negative residuals.

C. The mean of the residuals is always zero. This is a fundamental property of residuals in regression analysis. The sum of all residuals is zero, and when divided by the number of data points, the mean is also zero.

D. If the correlation is 0, it means there is no linear relationship between the variables. In this case, the residual plot would show a random scatter of points around zero, rather than a distinct pattern.
C
zhipu C. The mean of the residuals is always zero.

Explanation: In linear regression, the residuals are the differences between the observed values and the predicted values. One of the properties of the residuals in a well-fitted linear regression model is that their mean is always zero. This ensures that the regression line is the best fit in the least squares sense.

Here's a brief explanation of why the other options are incorrect:

A. Influential scores can have large residuals, but not all influential scores necessarily have large residuals. Influence is more about how much a point affects the slope of the regression line, not just the size of the residual.

B. While a good linear model might have residuals that are evenly distributed around zero, it is not required that the number of positive residuals exactly equals the number of negative residuals. What matters is that the mean of the residuals is zero.

D. If the correlation is 0, it means there is no linear relationship between the variables. However, this does not imply a distinct pattern in the residual plot; it might just show random scatter around the horizontal axis.

Therefore, the correct answer is C.
C
gpto1 C C
deepseekv3 C. The mean of the residuals is always zero.

This is a fundamental property of regression lines. The residuals (the differences between the observed and predicted values) always sum to zero, meaning their mean is zero.
C