Logistic Regression: A Self-learning Text, Third Edition (Statistics in the Health Sciences)

B. Correlation: a standardized measure of covariance that is scale-free. rxy¼ covðX;YÞ sXsY i. Correlation values range from1to ...

i. A mean–variance relationship for the responses is specified. ii. The full likelihood is not specified. VI. GEE models(pages 5 ...

ii. The correlation is assumed to depend on the interval of time between responses. iii. AR1is a special case of the autoregress ...

ii. Empirical (robust) estimators, which are an adjustment of model-based estimators: a. Make use of the actual correlations bet ...

C. Quasi-likelihood estimating equations follow the same form as score equations and thus are called “score-like”equations. i. F ...

a. in a GEE logistic regression: var(Y)¼fm(1m). b. if different from 1, the scale factor (f) will affect the estimated standard ...

Practice Exercises Questions 1–5 pertain to identifying the following correla- tion structures that apply to clusters of four re ...

The estimating equations used for GEE models have a similar structure to those score equations but are generalized to accommodat ...

Answers to Practice Exercises Exchangeable correlation structure Stationary 1-dependent correlation structure Independent corre ...

15 GEE Examples n Contents Introduction 540 Abbreviated Outline 540 Objectives Presentation 542 Detailed Outline 558 Practice Ex ...

Introduction In this chapter, we present examples of GEE models applied to three datasets containing correlated responses. The e ...

Objectives Upon completing this chapter, the learner should be able to: State or recognize examples of correlated responses. St ...

Presentation I. Overview Examples: Modeling outcomes with dichotomous correlated responses FOCUS Three examples are presented: ...

Independent variables: BIRTHWGT (in grams) GENDER DIARRHEA¼ 1 if symptoms present in past month 0 otherwise 8 >< >: DIA ...

Output presented:  ^bh;s^bh(empirical), and Wald testP-values  “Working” correlation matrix (Ci) containingr^ Sample: K¼168 in ...

Model 1:AR1 correlation structure Variable Coefficient Empirical Std Err Wald p-value INTERCEPT 1.3978 1.1960 0.2425 BIRTHWGT  ...

r^j;jþ 1 ¼ 0 : 5254 r^j;jþ 2 ¼ð 0 : 5254 Þ^2 ¼ 0 : 2760 r^j;jþ 3 ¼ð 0 : 5254 Þ^3 ¼ 0 : 1450 Model 2:Exchangeable correlation str ...

Fixed structure:rprespecified, not estimated In Model 3,rfixed at 0.55 for con- secutive months; 0.30 for noncon- secutive month ...

Independent correlation structure: two models Model 4. Uses empiricals^b; fnot fixed Model 5. Uses model-baseds^b; ffixed at 1 B ...

Model 5:Standard logistic regres- sion (naive model) Variable Coefficient Model-based Std Err Wald p-value INTERCEPT 1.4362 0.6 ...