DemoKin uses matrix demographic methods to compute expected (average)
kin counts from demographic rates under a range of scenarios and
assumptions. The package is an R-language implementation of Caswell
(2019, 2020, 2022), and Caswell and Song (2021). It draws on previous
theoretical development by Goodman, Keyfitz and Pullum (1974).
Download the stable version from CRAN:
install.packages("DemoKin")Or you can install the development version from GitHub:
# install.packages("devtools")
devtools::install_github("IvanWilli/DemoKin")Consider an average Swedish woman called ‘Focal.’ For this exercise, we assume a female closed population in which everyone experiences the Swedish 2015 mortality and fertility rates at each age throughout their life; i.e., the ‘time-invariant’ assumption in Caswell (2019).
We then ask:
What is the expected number of relatives of Focal over her life course?
Let’s explore this using the Swedish data already included with
DemoKin.
library(DemoKin)
swe_surv_2015 <- swe_px[,"2015"]
swe_asfr_2015 <- swe_asfr[,"2015"]
swe_2015 <- kin(p = swe_surv_2015, f = swe_asfr_2015, time_invariant = TRUE)p is the survival probability by age from a life table and f are the
age specific fertility ratios by age (see ?kin for details).
Now, we can visualize the implied kin counts (i.e., the average number
of living kin) of Focal at age 35 using a network or ‘Keyfitz’ kinship
diagram with the function plot_diagram:
# We need to reformat the data a little bit
kin_total <- swe_2015$kin_summary
# Keep only data for Focal's age 35
kin_total <- kin_total[kin_total$age_focal == 35 , c("kin", "count_living")]
names(kin_total) <- c("kin", "count")
plot_diagram(kin_total, rounding = 2)
Relatives are identified by a unique code:
| DemoKin | Labels_female | Labels_male | Labels_2sex |
|---|---|---|---|
| coa | Cousins from older aunts | Cousins from older uncles | Cousins from older aunts/uncles |
| cya | Cousins from younger aunts | Cousins from younger uncles | Cousins from younger aunts/uncles |
| c | Cousins | Cousins | Cousins |
| d | Daughters | Brothers | Siblings |
| gd | Grand-daughters | Grand-sons | Grand-childrens |
| ggd | Great-grand-daughters | Great-grand-sons | Great-grand-childrens |
| ggm | Great-grandmothers | Great-grandfathers | Great-grandfparents |
| gm | Grandmothers | Grandfathers | Grandparents |
| m | Mother | Father | Parents |
| nos | Nieces from older sisters | Nephews from older brothers | Niblings from older siblings |
| nys | Nieces from younger sisters | Nephews from younger brothers | Niblings from younger siblings |
| n | Nieces | Nephews | Niblings |
| oa | Aunts older than mother | Uncles older than fathers | Aunts/Uncles older than parents |
| ya | Aunts younger than mother | Uncles younger than father | Aunts/Uncles younger than parents |
| a | Aunts | Uncles | Aunts/Uncles |
| os | Older sisters | Older brothers | Older siblings |
| ys | Younger sisters | Younger brothers | Younger siblings |
| s | Sisters | Brothers | Siblings |
For more details, including an extension to time-variant rates, deceased
kin, and multi-state models in a one-sex framework, see the
Reference_OneSex
vignette; also accessible from DemoKin:
vignette("Reference_OneSex", package = "DemoKin"). For two-sex models,
see the
Reference_TwoSex
vignette; also accessible from DemoKin:
vignette("Reference_TwoSex", package = "DemoKin"). If the vignette
does not load, you may need to install the package as
devtools::install_github("IvanWilli/DemoKin", build_vignettes = T).
Williams, Iván; Alburez-Gutierrez, Diego; and the DemoKin team. (2021) DemoKin: An R package to implement demographic matrix kinship models. URL: https://github.com/IvanWilli/DemoKin.
We thank Silvia Leek from the Max Planck Institute for Demographic Research for designing the DemoKin logo. The logo includes elements that have been taken or adapted from this file, originally by Ansunando, CC BY-SA 4.0 via Wikimedia Commons. Sha Jiang provided useful comments for improving the package.
DemoKin is under constant development. If you’re interested in
contributing, please get in touch, create an issue, or submit a pull
request. We look forward to hearing from you!
Caswell, Hal. 2019. “The Formal Demography of Kinship: A Matrix Formulation.” Demographic Research 41 (September): 679–712. https://doi.org/10.4054/DemRes.2019.41.24.
———. 2020. “The Formal Demography of Kinship II: Multistate Models, Parity, and Sibship.” Demographic Research 42 (June): 1097–1146. https://doi.org/10.4054/DemRes.2020.42.38.
———. 2022. “The Formal Demography of Kinship IV: Two-Sex Models and Their Approximations.” Demographic Research 47 (September): 359–96. https://doi.org/10.4054/DemRes.2022.47.13.
Caswell, Hal, and Xi Song. 2021. “The Formal Demography of Kinship III: Kinship Dynamics with Time-Varying Demographic Rates.” Demographic Research 45 (August): 517–46. https://doi.org/10.4054/DemRes.2021.45.16.
Goodman, Leo A, Nathan Keyfitz, and Thomas W. Pullum. 1974. “Family Formation and the Frequency of Various Kinship Relationships.” Theoretical Population Biology, 27. https://doi.org/10.1016/0040-5809(74)90049-5.
