ci.cum {Epi}R Documentation

Compute cumulative sum of estimates.

Description

Computes the cumulative sum of a set of parameter functions and the standard error of it. Optionally the exponential is applied to the parameter function before it is cumulated.

Usage

ci.cum( obj,
    ctr.mat = NULL,
     subset = NULL,
       intl = 1,
      alpha = 0.05,
        Exp = TRUE,
       zero = TRUE )

Arguments

obj A model object.
ctr.mat Contrast matrix to form .
subset Subset of the parameters to which ctr.mat should be applied.
intl Interval length for the cumulation. Either a constant or a numerical vector of length nrow(ctr.mat).
alpha Significance level used when computing confidence limits.
Exp Should the paramter function be exponentiated before it is cumulated?
zero Should an initial row of 0s be added to the result?

Details

The purpose of this function is to compute cumulative rate based on a model for the rates. If the model is a multiplicative model for the rates, the purpose of ctr.mat is to return a vector of rates or log-rates when applied to the coefficients of the model. If log-rates are returned, the they should be exponentiated before cumulated, and since log-linear models are the most common the Exp parameter defaults to TRUE.

Value

A matrix with 4 columns: Estimate, lower and upper c.i. and standard error. The numebr of rows equals nrow(ctr.mat) if zero if FALSEo, otherwise nrow(ctr.mat)+1, because an initial row of 0s is added.

Author(s)

Bendix Carstensen, http://www.pubhealth.ku.dk/~bxc

See Also

See also ci.lin

Examples






[Package Epi version 0.5.6 Index]