Quantitative Aptitude - Correlation and Regression
Exam Duration: 45 Mins Total Questions : 30
Bivariate Data are the data collected for
- (a)
Two variables
- (b)
More than two variables
- (c)
Two variables simultaneously
- (d)
Two variables at different points of time
For a p x q classification of bivariate data, the maximum number of conditional distributions is
- (a)
p
- (b)
p+q
- (c)
pq
- (d)
p or q
_________ is concerned with measurement of the "Strength of association" between variables.
- (a)
Correlation
- (b)
Regression
- (c)
Both
- (d)
None
If the values of yare not affected by changes in the values of x, the variables are said to be
- (a)
Correlated
- (b)
Uncorrelated
- (c)
Both
- (d)
Zero
The correlation between Employment and Purchasing power is ___________
- (a)
Positive
- (b)
Negative
- (c)
Zero
- (d)
None of these
Neither y nor x can be estimated by a linear function of the other variable when r equals
- (a)
+ 1
- (b)
-1
- (c)
0
- (d)
None
The partial correlation coefficient lies between
- (a)
-1 and +1
- (b)
0 and +1
- (c)
-1 and 0
- (d)
None
If Y = a + bx, then what is the coefficient of correlation between x and y?
- (a)
1
- (b)
-1
- (c)
1 or -1 according as b>0 or b<0
- (d)
None of these
In case the correlation coefficient between two variables is 1, the relationship between the two variables would be
- (a)
Y = a+x
- (b)
Y = a+bx, b>O
- (c)
Y = a+bx, b<O
- (d)
Y = a+bx, both a and b being positive.
If a, b, c, d are constants such that a and c are of opposite signs and r is the correlation coefficient between X and Y, then the correlation coefficient between aX + band cY + d is -
- (a)
(a / c)r
- (b)
(c / a)r
- (c)
r +
- (d)
r -
Scatter diagram is considered for measuring
- (a)
Linear relationship between two variables
- (b)
Curvilinear relationship between two variables
- (c)
Neither (a) or (b)
- (d)
Both (a) and (b)
Which of the following statements is not false?
- (a)
Scatter diagram fails to measure the extent of relationship between the variables
- (b)
Scatter diagram can measure correlation only when the variables are having a linear relationship
- (c)
Scatter diagram can measure correlation only when the variables are having a non-linear relationship.
- (d)
None of these.
If the plotted points in a scatter diagram are evenly distributed, then the correlation is
- (a)
Zero
- (b)
Negative
- (c)
Positive
- (d)
(a)or (b)
Correlation coefficient between x and y = correlation coefficient between u and v
- (a)
True
- (b)
False
- (c)
Both
- (d)
None
Karl Pearson'scoefficient is defined from
- (a)
Ungrouped data
- (b)
Grouped data
- (c)
Both
- (d)
none
When r = 0 then cov(x,y) is equal to
- (a)
+ 1
- (b)
- 1
- (c)
0
- (d)
None of these.
Find the product moment correlation coefficient from the followinq information:
X | 2 | 3 | 5 | 5 | 6 | 8 |
Y | 9 | 8 | 8 | 6 | 5 | 3 |
- (a)
-0.93
- (b)
0.57
- (c)
-0.49
- (d)
0.73
What is the value of correlation coefficient Karl Pearson on the basis of the following data:
X | -4 | -3 | -2 | -1 | 0 | 1 | 2 | 3 | 4 |
Y | 18 | 11 | 6 | 3 | 2 | -3 | -6 | -11 | -18 |
- (a)
1
- (b)
-1
- (c)
0
- (d)
-0.5
If u + 5x = 6 and 3y - 7v = 20 and the correlation coefficient between x and y is 0.58 then what would be the correlation coefficient between u and v?
- (a)
0.58
- (b)
-0.58
- (c)
-0.84
- (d)
0.84
Let x1 , x2 , .....x3 , be the ranks of n individuals according to character A and y1, y2, .... y3be the ranks of the same individuals according to other character B such that Xi + Yi = n + 1, then the coefficients of rank correlation between the characters A and B is.
- (a)
-1
- (b)
1
- (c)
0
- (d)
None of these
If the sum of the squares of rank differences in the marks of 10 students in two students is 44, then the coefficient of rank correlation is ________
- (a)
0.78
- (b)
0.73
- (c)
0.87
- (d)
None
The regression analysis measures
- (a)
The degree of co-variability between X & Y
- (b)
The variation of series
- (c)
The variation of X series
- (d)
Functional relationship between X and Y
Since Blood Pressure of a person depends on age, we need consider
- (a)
The regression equation of Blood Pressure on age
- (b)
The regression equation of age on Blood Pressure
- (c)
Both (a) and(b)
- (d)
Either (a) or (b)
The difference between the observed value and the estimated value in regression analysis is known as
- (a)
Error
- (b)
Residue
- (c)
Deviation
- (d)
(a) or (b)
Correlation coefficient r lies between the regression coefficients byx and bxy
- (a)
True
- (b)
False
- (c)
Both
- (d)
None
R, bxy, byx all have________ sign
- (a)
Different
- (b)
Same
- (c)
Both
- (d)
None
The regression equation are 8x - 10y + 66 = 0 and 40 x - 18y = 214 find the coefficient of correlation
- (a)
4/5
- (b)
-4/5
- (c)
3/5
- (d)
-1
If the reqressive line of y on x and of x on y are given by 2x + 3y = -1 and 5x + 6y = -1 then the arithmetic means of x and y are given by
- (a)
(1, -1)
- (b)
(-1. 1)
- (c)
(-1, -1)
- (d)
(2,3)
Coefficient of determination is computed as
- (a)
r3
- (b)
1-r2
- (c)
1+r2
- (d)
r2
The coefficient of concurrent deviation for p pairs of observations was found to be 1/\(\sqrt 3\). If the number of concurrent deviations was found to be 6, then the value of p is
- (a)
10
- (b)
9
- (c)
8
- (d)
None of these