# Tag Info

1 vote

### Can we assume a form of heteroskedasticity and correlation within groups with the sample mean?

Estimation of the sample mean is equivalent to estimating the coefficient of an intercept-only model. Consequently, if you have violations of the usual $iid$ assumption when you calculate the sample ...
• 39.3k

• 101

### Percentage Change values for Prices in a given basked: Gemoetric mean vs arithmetic mean to get "mean" Prices

I think it makes sense to look at the differences rather than summarize the Before basket and the After basket. In a way, this is the same logic as a paired t-test or a paired Wilcoxon signed rank ...
• 9,173
1 vote

### Percentage Change values for Prices in a given basked: Gemoetric mean vs arithmetic mean to get "mean" Prices

We would use the geometric mean if it was the same good declining by different prices throughout time (which would be appropriate for averaging growth/decline rates for the same thing), but you have ...

### t-test where one sample has zero variance?

As others have already said, it would be better to address the issue with rounding to get the original data. However, if you have to work with the data you have here's another fairly simple option ...
• 3,770