问题


There is a single choice question about high school statistics. Answer the question by replying A, B, C or D.
Question: Which of the following statements about the correlation coefficient is true?
A. The correlation coefficient and the slope of the regression line may have opposite signs.
B. A correlation of 1 indicates a perfect cause-and-effect relationship between the variables.
C. Correlations of +0.87 and -0.87 indicate the same degree of clustering around the regression line.
D. Correlation applies equally well to quantitative and categorical data.
Answer:

答案

模型 模型答案 正确答案
金声玉亮2.0

C. Correlations of +0.87 and -0.87 indicate the same degree of clustering around the regression line.

Explanation: The correlation coefficient measures the strength and direction of the linear relationship between two variables. A correlation of +0.87 indicates a strong positive linear relationship, while a correlation of -0.87 indicates a strong negative linear relationship. Both correlations indicate the same degree of clustering around the regression line, but in opposite directions.

The other options are incorrect:

A. The correlation coefficient and the slope of the regression line will always have the same sign, as they both describe the direction of the linear relationship.

B. A correlation of 1 does not necessarily indicate a perfect cause-and-effect relationship between the variables. It only indicates a perfect positive linear relationship.

D. Correlation is typically used with quantitative data, not categorical data. While there are some methods for analyzing categorical data, such as chi-squared tests, correlation is not typically one of them.
C
deepseekr1

The correlation coefficient measures the strength and direction of a linear relationship. Here's the analysis of each option:

- **A**: The slope of the regression line is calculated as \( r \cdot \frac{s_y}{s_x} \), where \( r \) is the correlation coefficient and \( s_y, s_x \) are standard deviations (always positive). Thus, the slope's sign depends entirely on \( r \), making opposite signs impossible. **False**.

- **B**: A correlation of ±1 indicates a perfect linear relationship, not causation. Correlation does not imply causation, so even a perfect correlation cannot confirm cause-and-effect. **False**.

- **C**: The absolute value of \( r \) determines the strength of clustering around the regression line. Both +0.87 and -0.87 have the same absolute value, indicating identical clustering strength (only the direction differs). **True**.

- **D**: Correlation requires quantitative data. Categorical data (unless binary-coded) cannot compute Pearson’s \( r \). **False**.

**Answer: C**
C
gpto1 C C
GPT-4o C. Correlations of +0.87 and -0.87 indicate the same degree of clustering around the regression line. C
llama3.1-70B-Instruct

C
C
llama3.1-405B-Instruct

C. Correlations of +0.87 and -0.87 indicate the same degree of clustering around the regression line.

Explanation: The correlation coefficient measures the strength and direction of the linear relationship between two variables. A correlation of +0.87 indicates a strong positive linear relationship, while a correlation of -0.87 indicates a strong negative linear relationship. Both of these correlations indicate the same degree of clustering around the regression line, as the absolute value of the correlation coefficient (0.87) is the same in both cases.

The other options are incorrect:

A. The correlation coefficient and the slope of the regression line will always have the same sign, as they both describe the direction of the linear relationship.

B. A correlation of 1 indicates a perfect positive linear relationship, but it does not imply a cause-and-effect relationship between the variables.

D. Correlation is typically used with quantitative data, as it measures the strength and direction of the linear relationship between two continuous variables. While it is possible to use correlation with categorical data, it is not as common and may require additional considerations.
C
DeepSeek-Coder-V2 C C
Qwen2-72B-Instruct C C
baichuan4 C C
doubao C

A is incorrect as the correlation coefficient and the slope have the same sign. B is incorrect as a correlation of 1 indicates a perfect linear relationship, not necessarily a cause-and-effect relationship. D is incorrect as correlation is mainly for quantitative data. C is correct as the absolute value of the correlation coefficient indicates the strength of the relationship regardless of the sign.
C
minimax C. Correlations of +0.87 and -0.87 indicate the same degree of clustering around the regression line. C
kimi C. Correlations of +0.87 and -0.87 indicate the same degree of clustering around the regression line.

This statement is true because the absolute value of the correlation coefficient (also known as Pearson's r) indicates the strength of the linear relationship between two variables. A correlation of +0.87 indicates a strong positive linear relationship, while a correlation of -0.87 indicates a strong negative linear relationship. Both values suggest that the data points are tightly clustered around the line of best fit, regardless of the direction of the relationship.
C
wenxinyiyan C

Explanation:
A. The correlation coefficient and the slope of the regression line always have the same sign. If the correlation is positive, the slope is positive, indicating that as one variable increases, the other also increases. If the correlation is negative, the slope is negative, indicating that as one variable increases, the other decreases. So, A is false.

B. A correlation of 1 indicates a perfect linear relationship between the variables, but it does not indicate a cause-and-effect relationship. Correlation does not imply causation. So, B is false.

C. The absolute value of the correlation coefficient indicates the strength of the linear relationship between the variables. Both +0.87 and -0.87 have an absolute value of 0.87, indicating the same degree of clustering around the regression line. The only difference is the direction of the relationship (positive or negative slope). So, C is true.

D. Correlation applies only to quantitative data. It measures the strength and direction of the linear relationship between two quantitative variables. Correlation does not apply to categorical data. So, D is false.
C
zhipu C. Correlations of +0.87 and -0.87 indicate the same degree of clustering around the regression line.

Explanation:
- A. This is incorrect because the correlation coefficient and the slope of the regression line will have the same sign. If the correlation is positive, the slope is positive, and if the correlation is negative, the slope is negative.
- B. This is incorrect because a correlation of 1 indicates a perfect linear relationship, but it does not necessarily imply a cause-and-effect relationship.
- C. This is correct because the absolute value of the correlation coefficient indicates the strength of the relationship, regardless of the direction. Both +0.87 and -0.87 indicate a strong linear relationship with the same degree of clustering around the regression line.
- D. This is incorrect because correlation is typically used for quantitative data. While there are methods to assess relationships between categorical variables, the standard correlation coefficient (like Pearson's r) is not applicable to categorical data.
C
gpto1 C C
deepseekv3 C.

Explanation:
A. The correlation coefficient and the slope of the regression line always have the same sign, so this statement is false.
B. A correlation of 1 indicates a perfect linear relationship, not necessarily a cause-and-effect relationship, so this statement is false.
C. Correlations of +0.87 and -0.87 indicate the same strength of linear relationship, just in opposite directions, so this statement is true.
D. Correlation applies to quantitative data, not categorical data, so this statement is false.

Therefore, the correct answer is C.
C