I'm investigating if two of our processes are producing products with the same or different average measurements.
The first process has been used for a very long time and thus I have a sample size of 430 measurements for it.
The second process is very new and only has a sample size of 15 measurements for it.
I've done an F-test to compare the sample variances for what I have now, and I have no evidence to suggest the variances of the samples are different.
When I perform a t-test for the differences of averages, I get results that indicate a very significant difference between the two processes' measurements.
Is there any test out there that will achieve the goal as the t-test, but will also control for or take into account the very large sample size differences?