An application of mixture distributions in modelization of length of hospital stay

被引：34

作者：

Atienza, N. ^{[1
]}

Garcia-Heras, J. ^{[2
]}

Munoz-Pichardo, J. M. ^{[2
]}

Villa-Caro, R. ^{[3
]}

机构：

[1] Univ Seville, Dept Matemat Aplicada 1, ETS Ingn Informat, E-41012 Seville, Spain

[2] Univ Seville, Dept Estadistica & IO, Seville, Spain

[3] Univ Seville, Dept Anal Matemat, Seville, Spain

来源：

STATISTICS IN MEDICINE | 2008年 / 27卷 / 09期

关键词：

length of stay; diagnosis-related groups; finite mixture model; Gamma distribution; Weibull distribution; Lognormal distribution;

D O I：

10.1002/sim.3029

中图分类号：

Q [生物科学];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Length of hospital stay (LOS) is an important indicator of the hospital activity and management of health care. The skewness exhibited by this variable poses problems in statistical modeling. The aim of this work is to model the variable LOS within diagnosis-related groups (DRG) through finite mixtures of distributions. A mixture of the union of Gamma, Weibull and Lognormal families is used in the model, instead of a mixture of a unique distribution family. Some theoretical questions regarding the model, such as the identifiability and study of asymptotic properties of ML estimators, are analyzed. The EM algorithm is proposed for performing these estimators. Finally, this new proposed model is illustrated by using data from different DRGs. Copyright (C) 2007 John Wiley & Sons, Ltd.

引用

页码：1403 / 1420

页数：18

共 32 条

[1] On the consistency of MLE in finite mixture models of exponential families [J].

Atienza, N. ;

Garcia-Heras, J. ;

Munoz-Pichardo, J. M. ;

Villa-Caro, R. .

JOURNAL OF STATISTICAL PLANNING AND INFERENCE, 2007, 137 (02) :496-505

[2] A new condition for identifiability of finite mixture distributions [J].

Atienza, N. ;

Garcia-Heras, J. ;

Munoz-Pichardo, J. M. .

METRIKA, 2006, 63 (02) :215-221

[3] Consistency of maximum likelihood estimators in finite mixture models of the union of W-type families [J].

Atienza, N ;

García-Heras, J ;

Muñoz-Pichardo, J .

COMMUNICATIONS IN STATISTICS-THEORY AND METHODS, 2005, 34 (07) :1471-1485

[4] ESTIMATION OF PARAMETERS IN WEIBULL DISTRIBUTION [J].

BAIN, LJ ;

ANTLE, CE .

TECHNOMETRICS, 1967, 9 (04) :621-&

[5]

BRANDORFFNIELSE.O, 1965, J MATH ANAL APPL, V12, P115

[6] A NOTE ON THE CONSISTENCY AND MAXIMA OF THE ROOTS OF LIKELIHOOD EQUATIONS [J].

CHANDA, KC .

BIOMETRIKA, 1954, 41 (1-2) :56-61

[7]

CHANDRA S, 1977, SCAND J STAT, V4, P105

[8] MAXIMUM LIKELIHOOD FROM INCOMPLETE DATA VIA EM ALGORITHM [J].

DEMPSTER, AP ;

LAIRD, NM ;

RUBIN, DB .

JOURNAL OF THE ROYAL STATISTICAL SOCIETY SERIES B-METHODOLOGICAL, 1977, 39 (01) :1-38

[9] FIRM, PATIENT, AND PROCESS VARIABLES ASSOCIATED WITH LENGTH OF STAY IN 4 DISEASES [J].

FERNOW, LC ;

MCCOLL, I ;

MACKIE, C .

BMJ-BRITISH MEDICAL JOURNAL, 1978, 1 (6112) :556-559

[10]

Fetter RB., 1980, Med Care Res Rev, V18, pi

← 1 2 3 4 →