life.exp {asbio}

Mouse life expectancy data

Description

Weindruch et al. (1986) compared life expectancy of field mice given different diets. To accomplish this, the authors randomly assigned 244 mice to one of four diet treatments.

Usage

data(life.exp)

Format

A data frame with 244 observations on the following 2 variables.

lifespan

Lifespan in weeks

treatment

a factor with levels N/N85: Mice were fed normally both before and after weaning (the slash distinguishes pre and post weaning). After weaning the diet consisted of 85kcal/week, a conventional total for mice rearing, N/R40: Mice were fed normally before weaning, but were given a severely restricted diet of 40 kcal per week after feeding, N/R50: Mice were restricted to 50kcal per week before and after weaning, R/R50

: Mice were fed normally before weaning, but their diet was restricted to 50 kcal per week after weaning.

Source

Ramsey, F. L., and D. W. Schafer (1997) The Statistical Sleuth: A Course in Methods of Data Analysis. Duxbury Press, Belmont, CA.

References

Weindruch, R., Walford, R. L., Fligiel, S., and D. Guthrie (1986) The retardation of aging in mice by dietary restriction: longevity, cancer, immunity and lifetime energy intake. The Journal of Nutrition 116 (4): 641-54.

Examples

data(life.exp)
## maybe str(life.exp) ; plot(life.exp) ...