Krishnamoorthy and Yu (2004, Statistics and Probability Letters 66: 161-169) published a new approximate solution to the multivariate Behrens-Fisher problem. It is a modification of Nel and Van der Merwe's (1986, Communications in Statistics, Theory and Methods 15: 3719-3735) test. The test is invariant and identical to Welch's test for one-dimensional data. In this article, I describe all implementation of the test in Stata. The hotelmnm command allows you to perform the test easily and returns computed values for possible further computations.

I describe two utilities dealing with value labels. labeldup reports and optionally removes duplicate value labels. labelrename renames a value label. Both utilities, of course, preserve the links between variables and value labels and support multilingual datasets. Copyright 2005 by StataCorp LP.

Did you know about the floor() and ceil() functions added in Stata 8? Suppose that you want to round down in multiples of some fixed number.For concreteness, say, you want to round mpg in the auto data in multiples of 5 so that any values 10-14 get rounded to 10, any values 15-19 to 15, etc. mpg is simple, in that only integer values occur; in many other cases, we clearly have fractional parts to think about as well.Here is an easy solution: 5 * floor(mpg/5).floor() always rounds down to the integer less than or equal to its argument.The name floor is due to Iverson (1962), the principal architect of APL, who also suggested the expressive x notation.