咨询：scipy.stats默认ttest_ind是否为Welch's t-test及实现方法

Hey Emma,

Great question! Let me break this down clearly for you:

By default, when you run scipy.stats.ttest_ind(a, b, axis=0), you're executing the Student's t-test. This is because the function uses equal_var=True as its default parameter, which assumes that the two input samples have equal variances (homoscedasticity).

If you want to perform Welch's t-test (which does NOT assume equal variances between samples), all you need to do is set the equal_var parameter to False. Here's the exact code:

from scipy.stats import ttest_ind

# Replace a and b with your actual sample data
welch_result = ttest_ind(a, b, axis=0, equal_var=False)

A quick tip: Welch's t-test is often the safer choice when you're uncertain whether your two groups have equal variances, as it adjusts the degrees of freedom to account for potential variance differences between samples.

内容的提问来源于stack exchange，提问作者Emma