ISS PREVIOUS YEAR PAPER-2 2016 SOLUTION Q.NO. 4

ISS PREVIOUS YEAR PAPER-1 2016 SOLUTION Q.NO. 4 SET-A

UPSC ISS PYQ

 BEST COACHING FOR ISS

Question 4

The following data pertain to a test involving analysis of variance:

Estimate of population variance based on variance among the sample means = 18.50. Estimate of the population variance based on the variance within the samples = 12.50

The F-ratio for the sample is equal to:

Options:(a) 0.68(b) 1.48(c) 6.00(d) 31.00

Solution

Step 1: Concept of F-ratio in ANOVA

In Analysis of Variance (ANOVA), the F-ratio is defined as:

F = (Variance between samples) / (Variance within samples)

Step 2: Given Values

Variance among sample means (between samples) = 18.50, Variance within samples = 12.50

Step 3: Calculate F-ratio

F = 18.50 / 12.50

F = 1.48

Final Answer:- 1.48

Exam Insight (Very Important for ISS):

• Always remember: F = Between Variance / Within Variance

• If F > 1 → variability between groups is higher

• If F ≈ 1 → no significant difference

ISS PREVIOUS YEAR PAPER-1 2016 SOLUTION Q.NO. 4