主题：葫芦僧乱判葫芦案 -- 煮酒正熟

No one would use t-statistic or F-statistic to draw a conclusion without checking the underlying assumptions.

If I remember correctly, the underlying assumptions include (but may not be limited to):

1. Normality;

2. Equal variance (or stable variance);

3. Linearity (no curvature)

4. no influential outliers

I didn't check the Statistics text book so I may miss one or two.

Assumptions checking can be done by the method of residual analysis.

What I'm trying to say here is that, these are the very basic knowledge in statistics. I do not hold any degree in statistics, but I still know that I need to check these assumptions before drawing a conclusion. I just can't imagine that my colleague in the Advanced Analytics team who holds PhD in mathematics and statistics would NOT know this. I think you might have been too subjective in reaching a conclusion that what our company does is not correct.