Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Dr. JeFreda R. Brown is a financial ...

This section provides an overview of a likelihood-based approach to general linear mixed models. This approach simplifies and unifies many common statistical analyses, including those involving ...

In longitudinal data analysis, a correct specification of the within-subject covariance matrix cultivates an efficient estimation for mean regression coefficients. In this article, we consider robust ...

This paper investigates the value of observing a supplementary variable in an attempt to improve the dissection of a mixture of two normal distributions. The results can be employed in the ...

Caroline Banton has 6+ years of experience as a writer of business and finance articles. She also writes biographies for Story Terrace. Somer G. Anderson is CPA, doctor of accounting, and an ...