OvaryCancer {vcd}

Ovary Cancer Data

Description

Data from Obel (1975) about a retrospective study of ovary cancer carried out in 1973. Information was obtained from 299 women, who were operated for ovary cancer 10 years before.

Usage

data("OvaryCancer")

Format

A data frame with 16 observations and 5 variables.

Freq

frequency.

stage

factor indicating the stage of the cancer at the time of operation (early, advanced).

operation

factor indicating type of operation (radical, limited).

survival

factor indicating survival status after 10 years (yes, no).

xray

factor indicating whether X-ray treatment was received (yes, no).

Source

E. B. Andersen (1991), The Statistical Analysis of Categorical Data, Table 6.4.

References

E. B. Obel (1975), A Comparative Study of Patients with Cancer of the Ovary Who Have Survived More or Less Than 10 Years. Acta Obstetricia et Gynecologica Scandinavica, 55, 429-439.

E. B. Andersen (1991), The Statistical Analysis of Categorical Data. 2nd edition. Springer-Verlag, Berlin.

Examples

data("OvaryCancer")
tab <- xtabs(Freq ~ xray + survival + stage + operation, data = OvaryCancer)
ftable(tab, col.vars = "survival", row.vars = c("stage", "operation", "xray"))

## model: ~ xray * operation * stage + survival * stage
## interpretation: treat xray, operation, stage as fixed margins,
##   the survival depends on stage, but not xray and operation.
doubledecker(survival ~ stage + operation + xray, data = tab)
mosaic(~ stage + operation + xray + survival,
  split_vertical = c(FALSE, TRUE, TRUE, FALSE), data = tab, keep_aspect_ratio = FALSE,
  gp = gpar(fill = rev(grey.colors(2))))
mosaic(~ stage + operation + xray + survival,
  split_vertical = c(FALSE, TRUE, TRUE, FALSE), data = tab, keep_aspect_ratio = FALSE,
  expected = ~ xray * operation * stage + survival*stage)