Appendix A.38

Two-Sample t-Test (Welch's)

Compare means of two independent populations using Welch's t-test (unequal variances).

Two-Sample t-Test Calculator (Independent Samples)

Welch's t-test for comparing two population means

Sample 1

Sample 2

Null:
Alternative:
df:
49.30

Calculations

Difference
Standard Error
SE = 2.1365
Degrees of Freedom
df = 49.30
Test Statistic
t₀ = 2.0126

t-Distribution (df = 49.30)

-2.0122.0120t₀ = 2.01

Classical Approach

Critical Region: t < -2.012 or t > 2.012
t₀ = 2.0126 is in rejection region

P-Value Approach

P-value = 0.0496
P-value < α = 0.05

Reject H₀

At the α = 0.05 level, there is sufficient evidence to conclude that the two population means are different.