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We have previously demonstrated Stata implementation of bivariate ramdom effects meta-analysis of the sensitivity and specificity of a single binary diagnostic test by means of the midas module (Dwamena NASUG2007; Dwamena WCSUG 2007). In this presentation we extend our work to paired-comparison...
Persistent link: https://www.econbiz.de/10005103087
This presentation will demonstrate how to perform diagnostic meta-analysis using user-written macros midas and xtmidas for Stata versions 9 and 10 respectively. Both midas and xtmidas are comprehensive programs of statistical and graphical routines for undertaking meta-analysis of diagnostic...
Persistent link: https://www.econbiz.de/10005053583
Methods for meta-analysis of diagnostic test accuracy studies must, in addition to unobserved heterogeneity, account for covariate heterogeneity, threshold effects, methodological quality and small study bias, whic constitute the major threats to the validity of meta-analytic results. These have...
Persistent link: https://www.econbiz.de/10005053595
I present the new Stata 12 command, mi impute chained, to perform multivariate imputation using chained equations (ICE), also known as sequential regression imputation. ICE is a flexible imputation technique for imputing various types of data. The variable-by-variable specification of ICE allows...
Persistent link: https://www.econbiz.de/10009319515
Splines, including polynomials, are traditionally used to model nonlinear relationships involving continuous predictors. However, when they are included in linear models (or generalized linear models), the estimated parameters for polynomials are not easy for nonmathematicians to understand, and...
Persistent link: https://www.econbiz.de/10009320956
We will discuss SEM (structural equation modeling), not from the perspective of the models for which it is most often used--measurement models, confirmatory factor analysis, and the like--but from the perspective of how it can extend other estimators. From a wide range of choices, we will focus...
Persistent link: https://www.econbiz.de/10009320959
One of the aims of a phase I trial in oncology is to find the maximum tolerated dose. A set of doses is administered to participants starting from the lowest dose in increasing steps. To do this safely, the toxicity of each dose is assessed, and a decision is made about whether to proceed with...
Persistent link: https://www.econbiz.de/10009320960
It is well-known that the dummy variable estimator for the fixed-effects ordered logit model is inconsistent when T, the dimension of the panel, is fixed. This talk will review a range of alternative fixed-effects ordered logit estimators that are based on Chamberlain's fixed-effects estimator...
Persistent link: https://www.econbiz.de/10009320961
This talk presents a simple graphical device for visualization of patterns of income mobility. The device uses color palettes to picture information contained in transition matrices created from a fine partition of the marginal distributions. The talk explains how these graphs can be constructed...
Persistent link: https://www.econbiz.de/10009320962
Any analysis with incomplete data makes untestable assumptions about the missing data, and analysts are therefore urged to conduct sensitivity analyses. Ideally, a model is constructed containing a nonidentifiable parameter d, where d = 0 corresponds to the assumption made in the standard...
Persistent link: https://www.econbiz.de/10009320968