Tag: linear regression

Quizzes (2) Questions (75)

Questions Related to linear regression

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

If the regression coefficient of x on y is -1/3 and that of y on x is -3/4. Find the value of correlation coefficient between x and y___.

  1. -0.5

  2. 0.57

  3. 0.8

  4. None
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The correlation coefficient (r) is the geometric mean of the regression coefficients. Since both coefficients are negative, r must also be negative: r = -sqrt((-1/3) * (-3/4)) = -sqrt(1/4) = -0.5.

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

Correlation is______________.

  1. independent of change of origin

  2. independent of change of scale

  3. independent of origin and not of scale

  4. both (A) and (B)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Correlation is independent of change in both of scale and origin. Correlation simply measures the strength of association between two or more variables i.e. how strongly they are connected.

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

The angle between the two lines will be wider when the correlation between two variable is___________.

  1. less

  2. more

  3. equal

  4. very high
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The larger the angle between the two regression lines, less the degree of correlation between the two variables and similarly, the small the angle between two lines, the larger would be the degree of correlation between them.

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

If the regression coefficient bxy is 2.0, what is the value of a in the given equation 2.9X = aY + 15?

  1. 5.8

  2. 2.9

  3. 6.18

  4. 4.32
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The regression coefficient bxy is defined as the slope of the regression line of X on Y. In the equation 2.9X = aY + 15, we can rewrite it as X = (a/2.9)Y + (15/2.9). Since bxy = a/2.9 and bxy = 2.0, we have a/2.9 = 2.0, which means a = 5.8.

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

When there is a linear relationship between two numerical variables it can be measured by.

  1. Mean

  2. Mode

  3. Scatter diagram

  4. Coefficient of correlation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The coefficient of correlation is a statistical measure that quantifies the strength and direction of a linear relationship between two numerical variables.

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

What does correlation measure?

  1. Direction and intensity of relationship among variables

  2. It measures covariation, not causation

  3. Both A and B

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Correlation measures the strength and direction of the linear relationship between variables. It is also a fundamental principle in statistics that correlation indicates covariation rather than causation.

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

Which one of the following is false statement ?

  1. The sign of the regression coefficients are always the same.

  2. Correlation coefficient is the geometric mean of the regression coefficients.

  3. The co-variance between two variables divided by the product of their standard deviations produces the value of coefficient of correlation.

  4. Coefficient of correlation is independent of origin but not of sale.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The correlation coefficient is independent of both origin and scale. Therefore, the statement that it is not independent of scale is false.

Multiple choice business economics and quantitative methods linear regression aspects of correlation scatter graphs and correlation correlation

Which of the following is not true?

  1. Correlation means when value of one variable changes, the other variable also changes in the same direction

  2. Correlation studies and measures the direction and intensity of relationship among variables

  3. A scatter diagram visually presents the nature of association without giving any specific numerical value

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correlation does not imply that variables must move in the same direction; they can move in opposite directions (negative correlation). Therefore, the statement that correlation means they change in the same direction is not true.