This paper explores the following question: what kind of statistical guarantees can be given when doing variable variable in high dimensional models? In particular, we look at the error rates and power of some multi-stage regression methods. In the first stage we fit a set of candidate models. In the second stage we select one model by cross-validation. In the third stage we use hypothesis test...

This paper explores the following question: what kind of statistical guarantees can be given when doing variable selection in high dimensional models? In particular, we look at the error rates and power of some multi-stage regression methods. In the first stage we fit a set of candidate models. In the second stage we select one model by cross-validation. In the third stage we use hypothesis tes...

We consider the problem of selecting grouped variables (factors) for accurate prediction in regression. Such a problem arises naturally in many practical situations with the multi-factor ANOVA problem as the most important and well known example. Instead of selecting factors by stepwise backward elimination, we focus on estimation accuracy and consider extensions of the LASSO, the LARS, and the...

crop insurance is a main tool for coping up with different adversities in farming. the purpose followed in this study was to identify the major motivating and determinant factors of re-purchase of crop insurance by and among already insured farmers. survey research and multi sectional sampling procedures employed used to select farmers. the sample consisted of two groups of farmers: 1) currentl...

multi-echelon inventory systems are one of the most important and attractive areas in modelling supply chain management so that several researches and studies have been done about. in this paper, the total cost function of a two-echelon inventory system with central warehouse and many identical retailers controlled by continuous review inventory policy is estimated. we have assumed the demand i...