life.tab: Life table

In strandCet: Estimation of Biological Parameters from Stranded Cetaceans

Description

Performs a regular life table from a dataframe with ages and number of death individuals.

Usage

life.tab(x, n = 1000)

Arguments

x	A dataframe withtwo columns: Ages and number of deaths.
n	Inicial number of individuals in the theoretical population.

Details

Constructs a cohort life table from a dataframe with age classes and enumerated deaths.

Value

A dataframe with nine columns:

age	Age at the beginning of the interval.
Mx	Number of observed deaths at age x.
Sx	Number of survivors at age x in the observed cohort of sum(length(M)) individuals.
nx	Number of survivors at age x in a theoretical cohort starting with n individuals.
dx	Number of deaths at age x in a theoretical cohort starting with n individuals.
qx	Probability of death between ages x and x + n.
lx	Probability of survival to exact age x.
ex	Life expectancy at age x.
Zx	Instant death rate at age x

References

Preston, S.H., Heuveline, P. and Guillot, F. (2001). Demography: Measuring and modeling population processes. Oxford: Blackwell.

Examples

life.tab(cetaceans)

strandCet documentation built on May 1, 2019, 8:19 p.m.