A researcher measures the following scores for a group of pe

A researcher measures the following scores for a group of people. The X variable is the number of errors on a math test, and the Y variable is the person’s level of satisfaction with his/her performance. (a) With such ratio scores, what should the researcher conclude about this relationship? (Hint: Compute something!) (b) How well will he be able to predict satisfaction scores using this relationship? Participant 1,2,3,4,5,6,7 Errors X 9,8,4,6,7,10,5Satisfaction Y 3,2,8,5,4,2,7

Solution

Let, X : the number of errors on a math test

Y : the person’s level of satisfaction with his/her performance

(a) With such ratio scores, what should the researcher conclude about this relationship?

In this question we calculate here correlation between X and Y to conclude about the relationship.

We can find correlation between X and Y using EXCEL syntax is,

Plug in the excel sheet X and Y.

=CORREL(array1 ,array2)

where, array1 is values of Y

array2 is values of X.

This will gives us the value -0.9439.

There is negative correlation between X and Y.

(b) How well will he be able to predict satisfaction scores using this relationship?

Here we find regression equation to predict satisfaction scores using this relationship.

The regression equation is,

Y = a + b*X

where, a is constant.

and b is slope.

EXCEL syntax for constant and slope is,

For a :

=INTERCEPT(known y\'s, known x\'s)

For b :

=SLOPE(known y\'s, known x\'s)

a = 11.6786

b = -1.0357

Y = 11.6789 - 1.0357*X