La correlación es una medida estadística que permite conocer el grado de asociación lineal entre dos variables cuantitativas u ordinales (X, Y). También determina la fuerza y dirección toma esta relación mediante cálculo del coeficiente correlación, cuyo resultado puede variar en intervalo [-1, +1]. Entre más cercano a 1 sea mayor asociación. Cuando aleatoria o no existe, tiende cero. Los coefi...

BACKGROUND Despite several polysomnographic studies on periodic leg movements (PLM) in healthy sleep, data on the prevalence and characteristics of periodic arm movements (PAM) in normal subjects are lacking. We aimed to investigate PAM and their association with PLM during wakefulness and sleep in healthy subjects. METHODS Ninety-one participants underwent video-polysomnography according to ...

For many years, therapists have assumed a relationship between impairment and disability. More recently, researchers have begun to examine this assumption. "Motor Function and Activities of Daily Living Assessments: A Study of Three Tests for Persons With Hemiplegia" by Filiatrault, Arsenault, Dutil, and Bourbonnais (AjOT, September 1991, pp. 806-810) is a laudable example of such an examinatio...

Spearman distance is a permutation distance which might prove useful for coding, e.g. for codes on permutations. It turns out, however, that the Spearman geometry of strings is rather unruly from the point of view of error correction and error detection, and special care has to be taken to discriminate between the two notions of codeword distance and codeword distinguishability. All of this str...