Question24 What is the correlation between stocks B and C? Select one alternative: a. 0 (zero) b. 0.375 c. 0.573 d. 0.753 ResetMaximum marks: 1 Flag question undefined单项选择题
A
a. 0 (zero)
B
b. 0.375
C
c. 0.573
D
d. 0.753

Question

Question24 What is the correlation between stocks B and C? Select one alternative: a. 0 (zero) b. 0.375 c. 0.573 d. 0.753 ResetMaximum marks: 1 Flag question undefined

BlackTom AI · Accepted Answer

Correlation = Cov(B,C) ÷ (σB × σC). This is the defining formula relating covariance and standard deviations to the Pearson correlation coefficient.

1) Relevant knowledge points and concepts
- Covariance measures joint variability but is scale-dependent. Correlation standardizes covariance, giving a unitless measure between −1 and 1: ρ(B,C) = Cov(B,C) / (σBσC).
- Standard deviation σ is the square root of variance: σ = √Var.

2) Complete reasoning step by step
- Take the covariance between B and C from the data and the variances of B and C to compute their standard deviations.
- Compute σB = √Var(B) and σC = √Var(C).
- Compute the product σB × σC.
- Divide Cov(B,C) by that product to get ρ(B,C).

3) Intermediate calculations (values taken from the dataset/covariance table)
- Given: Cov(B,C) = 0.00086.
- Given: Var(B) = 0.0016 → σB = √0.0016 = 0.04.
- Given: Var(C) = 0.00140625 → σC = √0.00140625 = 0.0375.
- Product of standard deviations: σB × σC = 0.04 × 0.0375 = 0.0015.
- Correlation: ρ(B,C) = 0.00086 ÷ 0.0015 = 0.573333... ≈ 0.573.

4) Why the correct answer is correct
- The numeric result directly follows from the Pearson formula using the dataset values. The standardized ratio 0.573 indicates a moderate positive linear relationship between stocks B and C. All computations are algebraically straightforward and shown above.

5) Why the other options are incorrect
- a) 0 would imply no linear relationship; calculation yields 0.573, so a) is wrong.
- b) 0.375 is substantially lower than the computed 0.573; it does not match the covariance and SDs.
- d) 0.753 is higher than the computed value; the correct standardized ratio is 0.573, not 0.753.

6) Conclusion
- The computed correlation between stocks B and C is 0.573, so the correct choice is c. 0.573.

Question24 What is the correlation between stocks B and C? Select one alternative: a. 0 (zero) b. 0.375 c. 0.573 d. 0.753 ResetMaximum marks: 1 Flag question undefined单项选择题

类似问题

The birth weight and weight at age 21 of eight women are given in the table below. [table] Birth weight (kg) | 1.9 | 2.4 | 2.6 | 2.7 | 2.9 | 3.2 | 3.4 | 3.6 Weight at 21 (kg) | 47.6 | 53.1 | 52.2 | 56.2 | 57.6 | 59.9 | 55.3 | 56.7 [/table] The value of the correlation coefficient is closest to:

The scatterplot below represents percent of lean body mass and resting pulse rate. Is there a linear relationship visible? If so, what would you expect the correlation coefficient to be?

The birth weight and weight at age 21 of eight women are given in the table below. The value of the correlation coefficient is closest to:

Two variables are expected to have a linear relationship. The X variable is called "Explanatory" and the Y variable is called "Response" in R. The scatterplot is provided below. What is the expected value of the correlation coefficient?

Which one of the following correlations must be correct?

Suppose that a scatter diagram depicts a relationship between two variables that can be summarized by a straight line. The correlation coefficient is computed and results in a value of –0.73. Which of the following statements is NOT true?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单