Question

ociation bet i Data Table pretation of is as neede Student Study Time GPA on error. Skipped predict yig WN- QONOMN- nt of variabili GPA. % 00 O Print Done

Answer 1

Part(a)

The correlation coefficient r is given as follows:

Σ(; – 3)(yi - y) = 16.275

Σ(t; – 1)2 = 397.5

Σ(yi - y)2 = 1.109

Thus,

r = 16.275 ==0.7752 397.5. 1.109

Thus, the correlation is 0.7752

Rounding to two decimal places, correlation is 0.78

The interpretation of r is since r is positive the more time a student devotes to studying the more likely it is that he/she will have a higher GPA. Thus, the correct answer is E.

Part(b)

Rounding to 2 decimal places r^2 = 0.60

Prediction error = 1-r^2 = 1-0.6009 = 0.3991 = 39.91%

Rounding to a whole number prediction error = 40%

Variability in GPA 60.09% can be explained by the linear relationship between study time

Rounding to a whole number, the answer is 60%