# A practical approach for comparing means of two groups without equal variance assumption.

Journal Article

In this paper we consider two-groups of i.i.d. normally distributed random variables (N(mu(x),sigma(x) (2)) and N(mu(y),sigma(y) (2))) without assuming equal variance (sigma(x) (2) = sigma(y) (2)). We propose a simple method for constructing confidence bounds based on Howe's approximation I. Its applications in parallel clinical trial (testing H(0) : mu(x)-mu(y)=0 versus H(1) : mu(x)-mu(y)<0) and parallel bioequivalence (BE) trial (testing H(0):mid R:mu(x)-mu(y)mid R:delta versus H(1):mid R:mu(x)-mu(y)mid R:

### Full Text

### Duke Authors

### Cited Authors

- Wang, H; Chow, S-C

### Published Date

- October 30, 2002

### Published In

### Volume / Issue

- 21 / 20

### Start / End Page

- 3137 - 3151

### PubMed ID

- 12369087

### International Standard Serial Number (ISSN)

- 0277-6715

### Digital Object Identifier (DOI)

- 10.1002/sim.1238

### Language

- eng

### Conference Location

- England