Kellogg School of Management

Covariance and Correlation

In the first case, there is a strong upward-sloping relationship between X and Y; in the second case, no apparent relationship; in the third case, a strong downward-sloping relationship. Note the ...
Risk

Random matrix theory provides a clue to correlation dynamics

Harry Markowitz famously quipped that diversification is the only free lunch in investing. What he did not say is that this is only true if correlations are known and stable over time. Markowitz’s ...
insider.si.edu

Linear mixed models : a practical guide using statistical software / Brady T. West, Kathleen B. Welch, Andrzej T. Gałecki, University of Michigan, Ann Arbor, USA ; with ...

"First edition published in 2006." 1. Introduction -- What are linear mixed models (LMMs)? -- Models with random effects for clustered data -- Models for longitudinal or repeated-measures data -- A ...
Kellogg School of Management

Covariance and Correlation

In the first case, there is a strong upward-sloping relationship between X and Y; in the second case, no apparent relationship; in the third case, a strong downward-sloping relationship. Note the ...