Correlation - Online Test
Q1. Coefficient of correlation is also known as product moment correlation.
Answer : Option C
Explaination / Solution:
As it is the product of two different random variables.also in denominator there is product of standard deviation
Q2. If r is near to zero (i.e.) 0.1,-0.1, (or) 0.2 there is
Answer : Option A
Explaination / Solution:
As the range of correlation is 0 to 1(less to high degree correlation)
Q3. Formula for calculating correlation from the assumed mean method is
Answer : Option B
Explaination / Solution:
This is the correct formula to calculate Karl Pearson's correlation coefficient. It will take a value ranging from -1 to +1. Positive values of correlation coefficient indicate positive relationship between the two variables, while negative values are indicative of a negative relationship.
Q4. What is the range of simple correlation coefficient?
Answer : Option B
Explaination / Solution:
Because the correlation between two variables can be negative or positive or no relation
Q5. Which method of measuring correlation measures any type of relationship?
Answer : Option B
Explaination / Solution:
Only karl Pearson method shows relation between two variables and spearman correlation shows ordinal aspects of the variables
Q6. If cov(x,y) = 0 then
Answer : Option C
Explaination / Solution:
As correlation is zero, the variables are not related with each other
Q7. If D2 = 0 rank correlation is
Answer : Option D
Explaination / Solution:
If it is so then the fraction part will be zero and when zero is subtracted from1 we will get 1.
Q8. Correlation coefficient is independent of change of
Answer : Option D
Explaination / Solution:
By change of scale we mean that all values of X and y series are multiplied or divided by some constant.by change of origin we mean that a constant is subtracted from all values of x and y series if the scale and origin of X and y series are changed the value of r remain unchanged
Q9. Rank Correlation was found by
Answer : Option B
Explaination / Solution:
In 1904, Charles Edward Spearman developed the formula to calculate coefficient of correlation of qualitative variables.
Q10. The coefficient of correlation
Answer : Option C
Explaination / Solution:
Because the two series can be related directly or Inversely.
