sur.freq {Biodem}

Calculates surnames frequency tables

Description

“sur.freq”calculates surnames frequency tables starting from raw marriage data or equivalent sources (i.e. birth registrations)

Usage

sur.freq(x,pop,mal.sur,fem.sur,freq.table="total")

Arguments

x

is a data frame in which every row corresponds to a different marriage record. The data frame must contain: a a column reporting the population in which the marriage was recorded; b a column containing male surnames; c a column containing female surnames

pop

is the name of the column in the data frame that reports the population in which the marriage was recorded

mal.sur

is the name of the column in the data frame that contains male surnames

fem.sur

is the name of the column in the data frame that comtains female surnames

freq.table

character string specifying the type of surname frequency table to be calculated. The available options are: "males" (table calculated using only male surnames); "females" (table calculated using only female surnames); "total" (table calculated using all the surnames); "marriages" (tables calculated using observed pairs of surnames in each population). The default option is "total".

Details

“sur.freq” is specifically written to derive surname frequency tables from marriage data, or, more generally, data in which appear couples of related surnames, as birth records etc.

Value

A single table of surname frequencies ("male", "female", "total" options) or tables of observed pairs of surnames frequencies for each population ("marriages" option)

Note

Surname frequency tables produced with “sur.freq” are intended to be used as an argument for other functions to investigate the bio-demographic structure of populations. In particular, the "male", "female" and "total" options produce tables to be used in inter-population analyses (maesures of kinship/distance between populations, etc.); the "marriage" option produces tables to be used in intra-population analyses (inbreeding levels etc.). Tables of surname frequencies can also be obtained from simple lists of surnames (i.e. telephone directories, etc.) using the function “table”; for further explanations see the info for the "surnames" data set.

Author(s)

Federico C. F. Calboli and Alessio Boattini [e-mail]

References

Lasker, G. W. 1985. Surnames and genetic structure. Cambridge University Press. Cambridge, England

See Also

mar.iso for the calculation of Marital Isonymy coefficients from tables of observed pairs of surnames frequencies, r.pairs fot the calculation of Repeated Pairs coefficients from tables of observed pairs of surnames frequencies, lasker and hedrick for the calculation of similarity indexes between populations from surnames frequency tables, surnames for an explanation on how to generate a surname frequency table starting from non-marriage like data

Examples

data(valley)
valley #a subset of a real marriage data base

# you can see that marriages correspond to rows in the data frame.
# Note that the data frame contains other columns 

tot <- sur.freq(valley,valley$PAR,valley$SURM,valley$SURF)
tot # a frequency table calculated above all the surnames
mal <- sur.freq(valley,valley$PAR,valley$SURM,valley$SURF,freq.table="males")
mal # a frequency table calculated above the male surnames
fem <- sur.freq(valley,valley$PAR,valley$SURM,valley$SURF,freq.table="females")
fem # a frequency table calculated above the female surnames
mar <- sur.freq(valley,valley$PAR,valley$SURM,valley$SURF,freq.table="marriages")
mar # frequency tables for the observed pairs of surnames in each population