What is "Discriminant hotelling"? Recently I have encountered the term Discriminant hotelling. And I have no idea what this term means. All I know is that this is in context with multivariable data analysis. I tried googling but in vain. So can someone explain to me what this term means?
 A: Discriminant hotelling or discriminant/hotelling is somewhat ambiguous (@amoeba) and seems to be poor word choice (@whuber). An example of that usage appears here. The context in that paper is the Hotelling's T-squared distribution, together with Discriminant function analysis. 
Hotelling's t-squared statistic is a generalization of Student's t statistic that is used in multivariate hypothesis testing. The overlap with discriminant analysis is hinted at in the presentation of Mahalanobis distance, which  is closely related to Hotelling's T-square distribution used for multivariate statistical testing and Fisher's Linear Discriminant Analysis that is used for supervised classification. 
Discriminant analysis and Hotelling's T$^2$: Beware: The combination of discriminant analysis and Hotelling's T$^2$ test is sometimes misused. One should not be surprised to find a statistically significant difference between two samples which have been chosen with the objective of maximizing distance in the first place! The division into two groups should ideally be based on independent evidence. Indeed, in the cited paper above, the classification was properly taken a priori.
