In this Journal, Lewis and colleagues introduced a new Reliable Change Index (RCI(WSD)), which incorporated the within-subject standard deviation (WSD) of a repeated measurement design as the standard error. In this note, two opposite errors in using WSD this way are demonstrated. First, being the standard error of measurement of only a single assessment makes WSD too small when practice effect...

As a nonstatistician, I have watched the discussion on this topic with interest (1–8). Dr. Curren-Everett and others make a clear statement that variability of results should always be reported using the standard deviation (SD) and not the standard error (SE). Others cited above variously agree and disagree with the guidelines published by Dr. Curren-Everett and others. The reasoning provided i...

PURPOSE To evaluate the association of computed tomography (CT) texture features of locally advanced rectal cancer with neoadjuvant chemoradiotherapy (CRT) response and disease-free survival (DFS). METHODS AND FINDINGS The institutional review board approved this retrospective study. 95 patients who received neoadjuvant CRT, followed by surgery, for locally advanced rectal cancer were include...

Let $a_1, \ldots, a_n \in \mathbb{R}$ satisfy $\sum_i a_i^2 = 1$, and let $\varepsilon_1, \varepsilon_n$ be uniformly random $\pm 1$ signs $X \sum_{i=1}^{n} a_i \varepsilon_i$. It is conjectured that \varepsilon_i$ has $\Pr[X \geq 1] 7/64$. The best lower bound so far $1/20$, due to Oleszkiewicz. In this paper we improve 6/64$.

In this paper a new Query Performance Prediction method is introduced. This method is based on the hypothesis that different score distributions appear for ‘hard’ and ‘easy’ queries. Following we propose a set of measures which try to capture the differences between both types of distributions, focusing on the dispersion degree among the scores. We have applied some variants of the classic stan...