This paper develops a nonparametric analysis for the sharp regression discontinuity (RD) design in which the continuous forcing variable may contain measurement error. We show that if the observable forcing variable contains measurement error, this error causes severe identification bias for the...

Hedge funds? (HF) assets under management (AUM) expanded at more than 20% per annum between 2000 and the mid-2008 peak of USD1.85 trillion. The 2008 Global Financial Crisis (GFC) led to a drastic industry contraction with an estimated 2,000 fund liquidations. Nonetheless, the industry?s AUM is...

This article reviews Multivariable Model-building: A Pragmatic Approach to Regression Analysis Based on Fractional Polynomials for Modeling Continuous Variables, by Patrick Royston and Willi Sauerbrei.

Assessing the instability of a multivariable model is important but is rarely done in practice. Model instability occurs when selected predictors--and for multivariable fractional polynomial modeling, selected functions of continuous predictors--are sensitive to small changes in the data....

There is increasing interest in the medical world in the possibility of tailoring treatment to the individual patient. Statistically, the relevant task is to identify interactions between covariates and treatments, such that the patient’s value of a given covariate influences how strongly (or...

We consider how to represent sigmoid-type regression relationships in a practical and parsimonious way. A pure sigmoid relationship has an asymptote at both ends of the range of a continuous covariate. Curves with a single asymptote are also important in practice. Many smoothers, such as...

In dose-response studies, the dose range is often restricted due to concerns over drug toxicity and/or efficacy. We derive optimal designs for estimating the underlying dose-response curve for a restricted or unrestricted dose range with respect to a broad class of optimality criteria. The...