R: Only for internal use.

poly3est {MCPAN} | R Documentation

## Only for internal use.

### Description

Poly-3- adjusted point and variance estimates for long term carcinogenicity data

### Usage

    poly3est(time, status, tmax, method = "BP", k=NULL)

### Arguments

`time` | a numeric vector of times of death of the individuals
`status` | a logical (or numeric, consisting of 0,1 only) vector giving the tumour status at time of death of each individual, where TRUE (1) = tumour present, FALSE (0) = no tumour present
`tmax` | a single numeric vector, the final time of the trial
`method` | a single charcter string, specifying the method for adjustment, with options: "BP" (Bailer Portier: assuming poly-3-adjusted rates are binomial variables), "BW" (Bieler, Williams: delta method as in Bieler-Williams (1993)) "ADD1" (as Bailer Portier, including an add1-adjustment on the raw tumour rates) "ADD2" (as Bailer Portier, including an add2-adjustment on the raw tumour rates following Agresti Caffo (2000) for binomials)
`k` | a single numeric value, the exponent to calculate survival adjusted proportions according to Bailer and Portier (1988), defaults to 3

### Details

Only for internal use of poly3test and poly3ci.

### Value

A list containing:

`Y` | number of tumours
`n` | number of individuals
`estimate` | poly-3-adjusted rates according to Bailer, Portier (1988)
`weight` | a vector of poly-3-adjusted weights, of length n
`estp` | poly-3-adjusted rate (according to method)
`nadj` | adjusted n (sum of weights)
`varp` | variance estimate (according to method)
`varcor` | variance estimate, if necessary corrected such that estimates of 0 can not occur

### Note

Please note, that appropriateness of the point estimates seriously depends on whether the assumptions in Bailer and Portier are met or not.

### References

Bailer, J.A. and Portier, C.J. (1988): Effects of treatment-induced mortality and tumor-induced mortality on tests for carcinogenicity in small samples. Biometrics 44, 417-431.

[Package MCPAN version 1.1-21 Index]