Package 'demography'

Title: Forecasting Mortality, Fertility, Migration and Population Data
Description: Functions for demographic analysis including lifetable calculations; Lee-Carter modelling; functional data analysis of mortality rates, fertility rates, net migration numbers; and stochastic population forecasting.
Authors: Rob Hyndman [aut, cre, cph] , Heather Booth [ctb] , Leonie Tickle [ctb] , John Maindonald [ctb], Simon Wood [ctb], R Core Team [ctb]
Maintainer: Rob Hyndman <[email protected]>
License: GPL (>= 3)
Version: 2.0.0.9000
Built: 2024-10-30 05:02:21 UTC
Source: https://github.com/robjhyndman/demography

Help Index


Forecasting mortality and fertility data

Description

Functions for demographic analysis including lifetable calculations, Lee-Carter modelling and functional data analysis of mortality rates.

Author(s)

Rob J Hyndman with contributions from Heather Booth, Leonie Tickle, John Maindonald, Simon Wood and the R Core Team.

Maintainer: <[email protected]>


Coerce a demogdata object to a data.frame object

Description

Coerce a demogdata object to a data.frame object

Usage

## S3 method for class 'demogdata'
as.data.frame(x, ...)

Arguments

x

Object to be coerced to a data frame.

...

Other arguments not used

Value

A data.frame object.

Examples

# coerce demogdata object to data.frame ----
as.data.frame(fr.mort)

Australian fertility data

Description

Age-specific fertility rates and female child-bearing population for Australia.

Format

Object of class demogdata containing the following components:

year

Vector of years

age

Vector of ages

rate

List containing one matrix with one age group per row and one column per year.

pop

Population data in same form as rate.

type

Type of object. In this case, “fertility”.

label

Character string giving area from which data are taken. In this case, “Australia”.

Details

Australian fertility rates and populations (1921-2002) for age groups (<20, 20-24, 25-29, 30-34, 35-39, 40-44, 45+). Data taken from v3.2b of the Australian Demographic Data Bank released 10 February 2005.

Author(s)

Rob J Hyndman

Source

The Australian Demographic Data Bank (courtesy of Len Smith).

Examples

plot(aus.fert)

Monotonic interpolating splines

Description

Perform cubic spline monotonic interpolation of given data points, returning either a list of points obtained by the interpolation or a function performing the interpolation. The splines are constrained to be monotonically increasing (i.e., the slope is never negative).

Usage

cm.spline(x, y = NULL, n = 3 * length(x), xmin = min(x), xmax = max(x), ...)

cm.splinefun(x, y = NULL, ...)

Arguments

x, y

vectors giving the coordinates of the points to be interpolated. Alternatively a single plotting structure can be specified: see xy.coords.

n

interpolation takes place at n equally spaced points spanning the interval [xmin, xmax].

xmin

left-hand endpoint of the interpolation interval.

xmax

right-hand endpoint of the interpolation interval.

...

Other arguments are ignored.

Details

These are simply wrappers to the splinefun function family from the stats package.

Value

cm.spline

returns a list containing components x and y which give the ordinates where interpolation took place and the interpolated values.

cm.splinefun

returns a function which will perform cubic spline interpolation of the given data points. This is often more useful than spline.

Author(s)

Rob J Hyndman

References

Forsythe, G. E., Malcolm, M. A. and Moler, C. B. (1977) Computer Methods for Mathematical Computations. Hyman (1983) SIAM J. Sci. Stat. Comput. 4(4):645-654. Dougherty, Edelman and Hyman 1989 Mathematics of Computation, 52: 471-494.

Examples

x <- seq(0,4,l=20)
y <- sort(rnorm(20))
plot(x,y)
lines(spline(x, y, n = 201), col = 2) # Not necessarily monotonic
lines(cm.spline(x, y, n = 201), col = 3) # Monotonic

Coherent functional demographic model for grouped data

Description

Fits a coherent functional model to demographic data as described in Hyndman, Booth & Yasmeen (2012). If two of the series in data are named male and female, then it will use these two groups. Otherwise it will use all available groups.

Usage

coherentfdm(data, order1 = 6, order2 = 6, ...)

Arguments

data

demogdata object containing at least two groups.

order1

Number of basis functions to fit to the model for the geometric mean.

order2

Number of basis functions to fit to the models for each ratio.

...

Extra arguments passed to fdm.

Value

A list (of class fdmpr) consisting of two objects: product (an fdm object containing a del for the geometric mean of the data) and ratio (a list of fdm objects, being the models for the ratio of each series with the geometric mean).

Author(s)

Rob J Hyndman

References

Hyndman, R.J., Booth, H., and Yasmeen, F. (2012) Coherent mortality forecasting: the product-ratio method with functional time series models. Demography, to appear. https://robjhyndman.com/publications/coherentfdm/

See Also

fdm, forecast.fdmpr

Examples

fr.short <- extract.years(fr.sm,1950:2006)
fr.fit <- coherentfdm(fr.short)
summary(fr.fit)
plot(fr.fit$product, components=3)

Combine two demogdata objects into one demogdata object

Description

Function to combine demogdata objects containing different years but the same age structure into one demogdata object. The standard use for this function will be combining historical data with forecasts. The objects must be of the same type.

Usage

combine.demogdata(obj1, obj2)

Arguments

obj1

First demogdata object (e.g., historical data).

obj2

Second demogdata object (e.g., forecasts).

Value

Object of class “demogdata” with the following components:

year

Vector of years

age

Vector of ages

rate

Matrix of rates with with one age group per row and one column per year.

pop

Matrix of populations in same form as rate and containing population numbers. This is only produced when both objects contain a pop component.

type

Type of object: “mortality”, “fertility” or “migration”.

label

Name of area from which the data are taken.

Author(s)

Rob J Hyndman

See Also

demogdata

Examples

fit <- fdm(fr.mort)
fcast <- forecast(fit, h=50)
france2 <- combine.demogdata(fr.mort,fcast)
plot(france2)
plot(life.expectancy(france2))
lines(rep(max(fr.mort$year)+0.5,2),c(0,100),lty=3)

Evaluation of demographic forecast accuracy

Description

Computes mean forecast errors and mean square forecast errors for each age level. Computes integrated squared forecast errors and integrated absolute percentage forecast errors for each year.

Usage

compare.demogdata(
  data,
  forecast,
  series = names(forecast$rate)[1],
  ages = data$age,
  max.age = min(max(data$age), max(forecast$age)),
  years = data$year,
  interpolate = FALSE
)

Arguments

data

Demogdata object such as created using read.demogdata containing actual demographic rates.

forecast

Demogdata object such as created using forecast.fdm or forecast.lca.

series

Name of series to use. Default: the first matrix within forecast$rate.

ages

Ages to use for comparison. Default: all available ages.

max.age

Upper age to use for comparison.

years

Years to use in comparison. Default is to use all available years that are common between data and forecast.

interpolate

If TRUE, all zeros in data are replaced by interpolated estimates when computing the error measures on the log scale. Error measures on the original (rate) scale are unchanged.

Value

Object of class "errorfdm" with the following components:

label

Name of region from which data taken.

age

Ages from data object.

year

Years from data object.

<error>

Matrix of forecast errors on rates.

<logerror>

Matrix of forecast errors on log rates.

mean.error

Various measures of forecast accuracy averaged across years. Specifically ME=mean error, MSE=mean squared error, MPE=mean percentage error and MAPE=mean absolute percentage error.

int.error

Various measures of forecast accuracy integrated across ages. Specifically IE=integrated error, ISE=integrated squared error, IPE=integrated percentage error and IAPE=integrated absolute percentage error.

life.expectancy

If data$type="mortality", function returns this component which is a matrix containing actual, forecast and actual-forecast for life expectancies.

Note that the error matrices have different names indicating if the series forecast was male, female or total.

Author(s)

Rob J Hyndman

See Also

forecast.fdm,plot.errorfdm

Examples

fr.test <- extract.years(fr.sm,years=1921:1980)
fr.fit <- fdm(fr.test,order=2)
fr.error <- compare.demogdata(fr.mort, forecast(fr.fit,20))
plot(fr.error)
par(mfrow=c(2,1))
plot(fr.error$age,fr.error$mean.error[,"ME"],
     type="l",xlab="Age",ylab="Mean Forecast Error")
plot(fr.error$int.error[,"ISE"],
     xlab="Year",ylab="Integrated Square Error")

Create demogdata object from raw data matrices

Description

Create demogdata object suitable for plotting using plot.demogdata and fitting an LC or BMS model using lca or an FDA model using fdm.

Usage

demogdata(data, pop, ages, years, type, label, name, lambda)

Arguments

data

Matrix of data: either mortality rates or fertility rates

pop

Matrix of population values of same dimension as data. These are population numbers as at 30 June of each year (i.e., the "exposures"). So, for example, the number of deaths is data*pop if data contains mortality rates.

ages

Vector of ages corresponding to rows of data.

years

Vector of years corresponding to columns of data.

type

Character string showing type of demographic series: either “mortality”, “fertility” or “migration”.

label

Character string of the name of area from which the data are taken.

name

Name of series: usually male, female or total.

lambda

Box-Cox transformation parameter.

Value

Object of class “demogdata” with the following components:

year

Vector of years

age

Vector of ages

rate

A list containing one or more rate matrices with one age group per row and one column per year.

pop

A list of the same form as rate but containing population numbers instead of demographic rates.

type

Type of object: “mortality”, “fertility” or “migration”.

label

label

lambda

lambda

Author(s)

Rob J Hyndman

See Also

read.demogdata


Extract some ages from a demogdata object

Description

Creates subset of demogdata object.

Usage

extract.ages(data, ages, combine.upper = TRUE)

Arguments

data

Demogdata object such as created using read.demogdata or smooth.demogdata.

ages

Vector of ages to extract from data.

combine.upper

If TRUE, ages beyond the maximum of ages are combined into the upper age group.

Value

Demogdata object with same components as data but with a subset of ages.

Author(s)

Rob J Hyndman

Examples

france.teens <- extract.ages(fr.mort,13:19,FALSE)
plot(france.teens)

Extract some years from a demogdata object

Description

Creates subset of demogdata object.

Usage

extract.years(data, years)

Arguments

data

Demogdata object such as created using read.demogdata or smooth.demogdata.

years

Vector of years to extract from data.

Value

Demogdata object with same components as data but with a subset of years.

Author(s)

Rob J Hyndman

Examples

france.1918 <- extract.years(fr.mort,1918)

Functional demographic model

Description

Fits a basis function model to demographic data. The function uses optimal orthonormal basis functions obtained from a principal components decomposition.

Usage

fdm(
  data,
  series = names(data$rate)[1],
  order = 6,
  ages = data$age,
  max.age = max(ages),
  method = c("classical", "M", "rapca"),
  lambda = 3,
  mean = TRUE,
  level = FALSE,
  transform = TRUE,
  ...
)

Arguments

data

demogdata object. Output from read.demogdata.

series

name of series within data holding rates (1x1).

order

Number of basis functions to fit.

ages

Ages to include in fit.

max.age

Maximum age to fit. Ages beyond this are collapsed into the upper age group.

method

Method to use for principal components decomposition. Possibilities are “M”, “rapca” and “classical”. See ftsm for details.

lambda

Tuning parameter for robustness when method="M".

mean

If TRUE, will estimate mean term in the model before computing basis terms. If FALSE, the mean term is assumed to be zero.

level

If TRUE, will include an additional (intercept) term that depends on the year but not on ages.

transform

If TRUE, the data are transformed with a Box-Cox transformation before the model is fitted.

...

Extra arguments passed to ftsm.

Value

Object of class “fdm” with the following components:

label

Name of country

age

Ages from data object.

year

Years from data object.

<series>

Matrix of demographic data as contained in data. It takes the name given by the series argument.

fitted

Matrix of fitted values.

residuals

Residuals (difference between observed and fitted).

basis

Matrix of basis functions evaluated at each age level (one column for each basis function). The first column is the fitted mean.

coeffs

Matrix of coefficients (one column for each coefficient series). The first column are all ones.

mean.se

Standard errors for the estimated mean function.

varprop

Proportion of variation explained by each basis function.

weights

Weight associated with each time period.

v

Measure of variation for each time period.

type

Data type (mortality, fertility, etc.)

y

The data stored as a functional time series object.

Author(s)

Rob J Hyndman

References

Hyndman, R.J., and Ullah, S. (2007) Robust forecasting of mortality and fertility rates: a functional data approach. Computational Statistics & Data Analysis, 51, 4942-4956. https://robjhyndman.com/publications/funcfor/

See Also

ftsm, forecast.fdm

Examples

france.fit <- fdm(fr.mort)
summary(france.fit)
plot(france.fit)
plot(residuals(france.fit))

Forecast functional demographic model.

Description

The coefficients from the fitted object are forecast using a univariate time series model. The forecast coefficients are then multiplied by the basis functions to obtain a forecast demographic rate curve.

Usage

## S3 method for class 'fdm'
forecast(
  object,
  h = 50,
  level = 80,
  jumpchoice = c("fit", "actual"),
  method = "arima",
  warnings = FALSE,
  ...
)

Arguments

object

Output from fdm.

h

Forecast horizon.

level

Confidence level for prediction intervals.

jumpchoice

If "actual", the forecasts are bias-adjusted by the difference between the fit and the last year of observed data. Otherwise, no adjustment is used.

method

Forecasting method to be used.

warnings

If TRUE, warnings arising from the forecast models for coefficients will be shown. Most of these can be ignored, so the default is warnings=FALSE.

...

Other arguments as for forecast.ftsm.

Value

Object of class fmforecast with the following components:

label

Name of region from which the data are taken.

age

Ages from lcaout object.

year

Years from lcaout object.

rate

List of matrices containing forecasts, lower bound and upper bound of prediction intervals. Point forecast matrix takes the same name as the series that has been forecast.

error

Matrix of one-step errors for historical data

fitted

Matrix of one-step forecasts for historical data

coeff

List of objects of type forecast containing the coefficients and their forecasts.

coeff.error

One-step errors for each of the coefficients.

var

List containing the various components of variance: model, error, mean, total and coeff.

model

Fitted model in obj.

type

Type of data: “mortality”, “fertility” or “migration”.

Author(s)

Rob J Hyndman

See Also

fdm, forecast.lca, forecast.ftsm.

Examples

france.fit <- fdm(fr.mort,order=2)
france.fcast <- forecast(france.fit,50)
plot(france.fcast)
models(france.fcast)

Forecast coherent functional demographic model.

Description

The product and ratio models from coherentfdm are forecast, and the results combined to give forecasts for each group in the original data.

Usage

## S3 method for class 'fdmpr'
forecast(object, h = 50, level = 80, K = 100, drange = c(0, 0.5), ...)

Arguments

object

Output from coherentfdm.

h

Forecast horizon.

level

Confidence level for prediction intervals.

K

Maximum number of years to use in forecasting coefficients for ratio components.

drange

Range of fractional differencing parameter for the ratio coefficients.

...

Other arguments as for forecast.fdm.

Value

Object of class fmforecast2 containing a list of objects each of class fmforecast. The forecasts for each group in the original data are given first. Then the forecasts from the product model, and finally a list of forecasts from each of the ratio models.

Author(s)

Rob J Hyndman

See Also

coherentfdm, forecast.fdm.

Examples

fr.short <- extract.years(fr.sm,1950:2006)
fr.fit <- coherentfdm(fr.short)
fr.fcast <- forecast(fr.fit)
plot(fr.fcast$male)
plot(fr.fcast$ratio$male, plot.type='component', components=3)
models(fr.fcast)

Forecast demogdata data using Lee-Carter method.

Description

The kt coefficients are forecast using a random walk with drift. The forecast coefficients are then multiplied by bx to obtain a forecast demographic rate curve.

Usage

## S3 method for class 'lca'
forecast(
  object,
  h = 50,
  se = c("innovdrift", "innovonly"),
  jumpchoice = c("fit", "actual"),
  level = 80,
  ...
)

Arguments

object

Output from lca.

h

Number of years ahead to forecast.

se

Method used for computation of standard error. Possibilities: “innovdrift” (innovations and drift) and “innovonly” (innovations only).

jumpchoice

Method used for computation of jumpchoice. Possibilities: “actual” (use actual rates from final year) and “fit” (use fitted rates).

level

Confidence level for prediction intervals.

...

Other arguments.

Value

Object of class fmforecast with the following components:

label

Region from which the data are taken.

age

Ages from object.

year

Years from object.

rate

List of matrices containing forecasts, lower bound and upper bound of prediction intervals. Point forecast matrix takes the same name as the series that has been forecast.

fitted

Matrix of one-step forecasts for historical data

Other components included are

e0

Forecasts of life expectancies (including lower and upper bounds)

kt.f

Forecasts of coefficients from the model.

type

Data type.

model

Details about the fitted model

Author(s)

Rob J Hyndman

See Also

lca, plot.fmforecast

Examples

france.lca <- lca(fr.mort, adjust="e0")
france.fcast <- forecast(france.lca, 50)
plot(france.fcast)
plot(france.fcast,'c')

French mortality data

Description

Age-specific mortality rates and population for France.

Format

Object of class demogdata containing the following components:

year

Vector of years

age

Vector of ages

rate

List of matrices containing rates with with one age group per row and one column per year. Matrices: total, female, male.

pop

Population data in same form as rate.

type

Type of object. In this case, “mortality”.

label

Character string giving area from which data are taken. In this case, “France”.

Details

fr.mort contains French mortality rates and populations (1899-2005) for ages 0-110. Data taken from the Human Mortality Database on 20 February 2008. fr.sm contains a smoothed version of fr.mort obtained using the smooth.demogdata function.

Author(s)

Rob J Hyndman

Source

The Human Mortality Database (http://www.mortality.org).

Examples

plot(fr.mort,years=1950:1997)

plot(fr.mort,years=1990,type='p',pch=1)
lines(fr.sm,years=1990)

Read data from HMD and construct a mortality demogdata object

Description

hmd.mx reads "Mx" (1x1) data from the Human Mortality Database (HMD https://www.mortality.org) and constructs a demogdata object suitable for plotting using plot.demogdata and fitting an LC or BMS model using lca or an FDA model using fdm. hmd.pop reads "Population" (1x1) data from the HMD and constructs a demogdata object suitable for plotting using plot.demogdata. hmd.e0 reads life expectancy at birth from the HMD and returns the result as a ts object.

Usage

hmd.mx(country, username, password, label = country)

hmd.e0(country, username, password)

hmd.pop(country, username, password, label = country)

Arguments

country

Directory abbreviation from the HMD. For instance, Australia = "AUS".

username

HMD username (case-sensitive)

password

HMD password (case-sensitive)

label

Character string giving name of country from which the data are taken.

Details

In order to read the data, users are required to create their account via the HMD website (https://www.mortality.org), and obtain a valid username and password.

Value

hmd.mx returns an object of class demogdata with the following components:

year

Vector of years

age

Vector of ages

rate

A list containing one or more rate matrices with one age group per row and one column per year.

pop

A list of the same form as rate but containing population numbers instead of demographic rates.

type

Type of object: “mortality”, “fertility” or “migration”.

label

label

hmd.pop returns a similar object but without the rate component. hmd.e0 returns an object of class ts with columns male, female and total.

Author(s)

Rob J Hyndman

See Also

demogdata,read.demogdata,plot.demogdata, life.expectancy

Examples

## Not run: 
norway <- hmd.mx("NOR", username, password, "Norway")
summary(norway)

## End(Not run)

Integrated Squared Forecast Error for models of various orders

Description

Computes ISFE values for functional time series models of various orders.

Usage

isfe(...)

## S3 method for class 'demogdata'
isfe(
  data,
  series = names(data$rate)[1],
  max.order = N - 3,
  N = 10,
  h = 5:10,
  ages = data$age,
  max.age = max(ages),
  method = c("classical", "M", "rapca"),
  fmethod = c("arima", "ar", "arfima", "ets", "ets.na", "struct", "rwdrift", "rw"),
  lambda = 3,
  ...
)

Arguments

...

Additional arguments control the fitting procedure.

data

demogdata object.

series

name of series within data holding rates (1x1)

max.order

Maximum number of basis functions to fit.

N

Minimum number of functional observations to be used in fitting a model.

h

Forecast horizons over which to average.

ages

Ages to include in fit.

max.age

Maximum age to fit.

method

Method to use for principal components decomposition. Possibilities are “M”, “rapca” and “classical”.

fmethod

Method used for forecasting. Current possibilities are “ets”, “arima”, “ets.na”, “struct”, “rwdrift” and “rw”.

lambda

Tuning parameter for robustness when method="M".

Value

Numeric matrix with (max.order+1) rows and length(h) columns containing ISFE values for models of orders 0:max.order.

Author(s)

Rob J Hyndman

References

Hyndman, R.J., and Ullah, S. (2007) Robust forecasting of mortality and fertility rates: a functional data approach. Computational Statistics & Data Analysis, 51, 4942-4956. https://robjhyndman.com/publications/funcfor/

See Also

fdm, forecast.fdm.


Model mortality or fertility data using Lee-Carter approach

Description

Lee-Carter model of mortality or fertility rates. lca produces a standard Lee-Carter model by default, although many other options are available. bms is a wrapper for lca and returns a model based on the Booth-Maindonald-Smith methodology.

Usage

lca(
  data,
  series = names(data$rate)[1],
  years = data$year,
  ages = data$age,
  max.age = 100,
  adjust = c("dt", "dxt", "e0", "none"),
  chooseperiod = FALSE,
  minperiod = 20,
  breakmethod = c("bai", "bms"),
  scale = FALSE,
  restype = c("logrates", "rates", "deaths"),
  interpolate = FALSE
)

bms(
  data,
  series = names(data$rate)[1],
  years = data$year,
  ages = data$age,
  max.age = 100,
  minperiod = 20,
  breakmethod = c("bms", "bai"),
  scale = FALSE,
  restype = c("logrates", "rates", "deaths"),
  interpolate = FALSE
)

Arguments

data

demogdata object of type “mortality” or “fertility”. Output from read.demogdata.

series

name of series within data containing mortality or fertility values (1x1)

years

years to include in fit. Default: all available years.

ages

ages to include in fit. Default: all available ages up to max.age.

max.age

upper age to include in fit. Ages beyond this are collapsed into the upper age group.

adjust

method to use for adjustment of coefficients ktktk_t kt. Possibilities are “dxt” (BMS method), “dt” (Lee-Carter method), “e0” (method based on life expectancy) and “none”. Defaults are “dxt” for bms() and “dt” for lca().

chooseperiod

If TRUE, it will choose the best fitting period.

minperiod

Minimum number of years to include in fitting period if chooseperiod=TRUE.

breakmethod

method to use for identifying breakpoints if chooseperiod=TRUE. Possibilities are “bai” (Bai's method computed using breakpoints in the strucchange package) and “bms” (method based on mean deviance ratios described in BMS).

scale

If TRUE, it will rescale bx and kt so that kt has drift parameter = 1.

restype

method to use for calculating residuals. Possibilities are “logrates”, “rates” and “deaths”.

interpolate

If TRUE, it will estimate any zero mortality or fertility rates using the same age group from nearby years.

Details

All mortality or fertility data are assumed to be in matrices of mortality or fertility rates within data$rate. Each row is one age group (assumed to be single years). Each column is one year. The function produces a model for the series mortality or fertility rate matrix within data$rate. Forecasts from this model can be obtained using forecast.lca.

Value

Object of class “lca” with the following components:

label

Name of region

age

Ages from data object.

year

Years from data object.

<series>

Matrix of mortality or fertility data as contained in data. It takes the name given by the series argument.

ax

Average deathrates across fitting period

bx

First principal component in Lee-Carter model

kt

Coefficient of first principal component

residuals

Functional time series of residuals.

fitted

Functional time series containing estimated mortality or fertility rates from model

varprop

Proportion of variance explained by model.

y

The data stored as a functional time series object.

mdev

Mean deviance of total and base lack of fit, as described in Booth, Maindonald and Smith.

Author(s)

Heather Booth, Leonie Tickle, John Maindonald and Rob J Hyndman.

References

Booth, H., Maindonald, J., and Smith, L. (2002) Applying Lee-Carter under conditions of variable mortality decline. Population Studies, 56, 325-336.

Lee, R.D., and Carter, L.R. (1992) Modeling and forecasting US mortality. Journal of the American Statistical Association, 87, 659-671.

See Also

forecast.lca, plot.lca, summary.lca, fdm

Examples

## Not run: 
france.LC1 <- lca(fr.mort, adjust="e0")
plot(france.LC1)
par(mfrow=c(1,2))
plot(fr.mort,years=1953:2002,ylim=c(-11,1))
plot(forecast(france.LC1,jumpchoice="actual"),ylim=c(-11,1))

france.bms <- bms(fr.mort, breakmethod="bai")
fcast.bms <- forecast(france.bms)
par(mfrow=c(1,1))
plot(fcast.bms$kt)

## End(Not run)

Estimate life expectancy from mortality rates

Description

All three functions estimate life expectancy from lifetable. The function flife.expectancy is primarily designed for forecast life expectancies and will optionally produce prediction intervals. Where appropriate, it will package the results as a forecast object which makes it much easier to product nice plots of forecast life expectancies. The e0 function is a shorthand wrapper for flife.expectancy with age=0.

Usage

life.expectancy(
  data,
  series = names(data$rate)[1],
  years = data$year,
  type = c("period", "cohort"),
  age = min(data$age),
  max.age = min(100, max(data$age))
)

flife.expectancy(
  data,
  series = NULL,
  years = data$year,
  type = c("period", "cohort"),
  age,
  max.age = NULL,
  PI = FALSE,
  nsim = 500,
  ...
)

e0(
  data,
  series = NULL,
  years = data$year,
  type = c("period", "cohort"),
  max.age = NULL,
  PI = FALSE,
  nsim = 500,
  ...
)

Arguments

data

Demogdata object of type “mortality” such as obtained from read.demogdata, or an object of class fmforecast such as the output from forecast.fdm or forecast.lca, or an object of class fmforecast2 such as the output from forecast.fdmpr.

series

Name of mortality series to use. Default is the first demogdata series in data.

years

Vector indicating which years to use.

type

Either period or cohort.

age

Age at which life expectancy is to be calculated.

max.age

Maximum age for life table calculation.

PI

If TRUE, produce a prediction interval.

nsim

Number of simulations to use when computing a prediction interval.

...

Other arguments passed to simulate when producing prediction intervals.

Value

Time series of life expectancies (one per year), or a forecast object of life expectancies (one per year).

Author(s)

Rob J Hyndman

See Also

lifetable

Examples

plot(life.expectancy(fr.mort),ylab="Life expectancy")

france.LC <- lca(fr.mort,adjust="e0",years=1950:1997)
france.fcast <- forecast(france.LC,jumpchoice="actual")
france.e0.f <- life.expectancy(france.fcast)

france.fdm <- fdm(extract.years(fr.mort,years=1950:2006))
france.fcast <- forecast(france.fdm)
## Not run: 
  e0.fcast <- e0(france.fcast,PI=TRUE,nsim=200)
  plot(e0.fcast)
## End(Not run)

life.expectancy(fr.mort,type='cohort',age=50)

Construct lifetables from mortality rates

Description

Computes period and cohort lifetables from mortality rates for multiple years.

Usage

lifetable(
  data,
  series = names(data$rate)[1],
  years = data$year,
  ages = data$age,
  max.age = min(100, max(data$age)),
  type = c("period", "cohort")
)

Arguments

data

Demogdata object such as obtained from read.demogdata, forecast.fdm or forecast.lca.

series

Name of series to use. Default is the first series in data[["rate"]].

years

Vector indicating which years to include in the tables.

ages

Vector indicating which ages to include in table.

max.age

Age for last row. Ages beyond this are combined.

type

Type of lifetable: period or cohort.

Details

For period lifetables, all years and all ages specified are included in the tables. For cohort lifetables, if ages takes a scalar value, then the cohorts are taken to be of that age in each year contained in years. But if ages is a vector of values, then the cohorts are taken to be of those ages in the first year contained in years.

For example, if ages=0 then lifetables of the birth cohorts for all years in years are computed. On the other hand, if ages=0:100 and years=1950:2010, then lifetables of each age cohort in 1950 are computed.

In all cases, qx=mx/(1+[(1ax)mx])q_x = m_x/(1+[(1-a_x)m_x]) as per Chiang (1984).

Warning: the code has only been tested for data based on single-year age groups.

Value

Object of class “lifetable” containing the following components:

label

Name of region from which data are taken.

series

Name of series

age

Ages for lifetable

year

Period years or cohort years

mx

Death rate at age x.

qx

The probability that an individual of exact age x will die before exact age x+1.

lx

Number of survivors to exact age x. The radix is 1.

dx

The number of deaths between exact ages x and x+1.

Lx

Number of years lived between exact age x and exact age x+1.

Tx

Number of years lived after exact age x.

ex

Remaining life expectancy at exact age x.

Note that the lifetables themselves are not returned, only their components. However, there is a print method that constructs (and returns) the lifetables from the above components.

Author(s)

Heather Booth, Leonie Tickle, Rob J Hyndman, John Maindonald and Timothy Miller

References

Chiang CL. (1984) The life table and its applications. Robert E Krieger Publishing Company: Malabar.

Keyfitz, N, and Caswell, H. (2005) Applied mathematical demography, Springer-Verlag: New York.

Preston, S.H., Heuveline, P., and Guillot, M. (2001) Demography: measuring and modeling population processes. Blackwell

See Also

life.expectancy

Examples

france.lt <- lifetable(fr.mort)
plot(france.lt)
lt1990 <- print(lifetable(fr.mort,year=1990))

france.LC <- lca(fr.mort)
france.fcast <- forecast(france.LC)
france.lt.f <- lifetable(france.fcast)
plot(france.lt.f)

# Birth cohort lifetables, 1900-1910
france.clt <- lifetable(fr.mort,type="cohort",age=0, years=1900:1910)

# Partial cohort lifetables for 1950
lifetable(fr.mort, years=1950)

Mean and median functions for data of class demogdata

Description

Computes mean or median of demographic rates for each age level.

Usage

## S3 method for class 'demogdata'
mean(x, series = names(x$rate)[1], transform = TRUE, na.rm = TRUE, ...)

## S3 method for class 'demogdata'
median(
  x,
  na.rm = FALSE,
  series = names(x$rate)[1],
  transform = TRUE,
  method = c("hossjercroux", "coordinate"),
  ...
)

Arguments

x

Demogdata object such as created using read.demogdata or smooth.demogdata.

series

Name of demogdata series to plot..

transform

Should transform of data be taken first?

na.rm

a logical value indicating whether NA values should be stripped before the computation proceeds.

...

Other arguments.

method

Method for computing the median. Either "coordinate" for a coordinate-wise median, or "hossjercroux" for the L1-median using the Hossjer-Croux algorithm.

Value

A list containing x=ages and y=mean or median rates.

Author(s)

Rob J Hyndman

References

Hossjer, O., and Croux, C. (1995) Generalized univariate signed rank statistics for testing and estimating a multivariate location parameter. Nonparametric Statistics, 4, 293-308.

Examples

plot(fr.mort)
lines(mean(fr.mort),lwd=2)
lines(median(fr.mort),lwd=2,col=2)

Show model information for the forecast coefficients in FDM models.

Description

The models for the time series coefficients used in forecasting fdm models are shown.

Usage

models(object, ...)

## S3 method for class 'fmforecast'
models(object, select = 0, ...)

## S3 method for class 'fmforecast2'
models(object, ...)

Arguments

object

Output from forecast.fdm or forecast.fdmpr.

...

Other arguments.

select

Indexes of coefficients to display. If select=0, all coefficients are displayed.

Author(s)

Rob J Hyndman

See Also

forecast.fdm, forecast.fdmpr.

Examples

## Not run: 
fr.short <- extract.years(fr.sm,1950:2006)
fr.fit <- fdm(fr.short,series="male")
fr.fcast <- forecast(fr.fit)
models(fr.fcast)

fr.fit <- coherentfdm(fr.short)
fr.fcast <- forecast(fr.fit)
models(fr.fcast,select=1:3)

## End(Not run)

Calculate net migration from mortality and fertility data

Description

Function to compute the net number of migrants in each year and for each age, based on the total population numbers, deaths and births in each year.

Usage

netmigration(mort, fert, startyearpop=mort, mfratio = 1.05)

Arguments

mort

Demogdata object of type "mortality"

fert

Demogdata object of type "fertility"

startyearpop

Demogdata object containing population data for first year of calculation.

mfratio

Male-female ratio to be used in simulating births.

Value

Object of class “demogdata” with the following components:

year

Vector of years

age

Vector of ages

rate

List containing matrices of net migration numbers (not "rates") with with one age group per row and one column per year. Names of matrices are the same as for mort$rate.

pop

List containing matrices of populations in same form as rate and containing population numbers.

type

Type of object. In this case, “migration”.

label

label from mort$label

Author(s)

Rob J Hyndman

See Also

demogdata

Examples

## Not run: 
require(addb)
aus.mig <- netmigration(australia,aus.fertility)
plot(aus.mig)
## End(Not run)

Plot age-specific demographic functions

Description

If plot.type="functions", then years are plotted using a rainbow palette so the earliest years are red, followed by orange, yellow, green, blue and indigo with the most recent years plotted in violet. If plot.type="time", then each age is shown as a separate time series in a time plot.

Usage

## S3 method for class 'demogdata'
plot(
  x,
  series = ifelse(!is.null(x$rate), names(x$rate)[1], names(x$pop)[1]),
  datatype = ifelse(!is.null(x$rate), "rate", "pop"),
  years = x$year,
  ages = x$age,
  max.age = max(x$age),
  transform = (x$type == "mortality"),
  plot.type = c("functions", "time", "depth", "density"),
  type = "l",
  main = NULL,
  xlab,
  ylab,
  ...
)

## S3 method for class 'demogdata'
lines(
  x,
  series = ifelse(!is.null(x$rate), names(x$rate)[1], names(x$pop)[1]),
  datatype = ifelse(!is.null(x$rate), "rate", ""),
  years = x$year,
  ages = x$age,
  max.age = max(x$age),
  transform = (x$type == "mortality"),
  plot.type = c("functions", "time", "depth", "density"),
  ...
)

## S3 method for class 'demogdata'
points(..., pch = 1)

Arguments

x

Demogdata object such as created using read.demogdata or smooth.demogdata.

series

Name of series to plot. Default: the first matrix within datatype.

datatype

Name of demogdata object which contains series. Default “rate”. Alternative: “pop”.

years

Vector indicating which years to plot. Default: all available years.

ages

Vector indicating which ages to plot. Default: all available ages.

max.age

Maximum age to plot. Default: all available ages.

transform

Should a transformation of the data be plotted? Default is TRUE if the object contains mortality data and datatype="rate", and FALSE otherwise.

plot.type

Type of plot: either “functions” or “time”.

type

What type of plot should be drawn. See plot for possible types.

main

Main title for the plot.

xlab

Label for x-axis.

ylab

Label for y-axis.

...

Other plotting parameters. In points.demogdata, all arguments are passed to lines.demogdata.

pch

Plotting character.

Value

None. Function produces a plot

Author(s)

Rob J Hyndman

Examples

plot(fr.mort)
par(mfrow=c(1,2))
plot(aus.fert,plot.type="time")
plot(aus.fert,plot.type="functions")

Plot differences between actuals and estimates from fitted demographic model

Description

Function produces a plot of errors from a fitted demographic model.

Usage

## S3 method for class 'errorfdm'
plot(x, transform = TRUE, ...)

Arguments

x

Object of class "errorfdm" generated by compare.demogdata.

transform

Plot errors on transformed scale or original scale?

...

Plotting parameters.

Author(s)

Rob J Hyndman

See Also

compare.demogdata

Examples

fr.fit <- lca(extract.years(fr.mort,years=1921:1980))
fr.error <- compare.demogdata(fr.mort, forecast(fr.fit,20))
plot(fr.error)

Plot forecasts from a functional demographic modell

Description

Type of plot depends on value of plot.type:

plot.type="function"

produces a plot of the forecast functions;

plot.type="components"

produces a plot of the basis functions and coefficients with forecasts and prediction intervals for each coefficient;

plot.type="variance"

produces a plot of the variance components.

Usage

## S3 method for class 'fmforecast'
plot(
  x,
  plot.type = c("function", "component", "variance"),
  vcol = 1:4,
  mean.lab = "Mean",
  xlab2 = "Year",
  h = 1,
  ...
)

## S3 method for class 'lca'
plot(x, ...)

Arguments

x

Output from forecast.ftsm, forecast.fdm or lca.

plot.type

Type of plot. See details.

vcol

Colors to use if plot.type="variance".

mean.lab

Label for mean component.

xlab2

x-axis label for coefficient time series.

h

If plot.type="variance", h gives the forecast horizon for which the variance is plotted.

...

Other arguments are passed to plot.demogdata (if plot.type=="function"), plot (if plot.type=="variance") or plot.ftsf (if plot.type=="component").

Value

None. Function produces a plot

Author(s)

Rob J Hyndman

See Also

fdm, lca, forecast.fdm

Examples

france.fcast <- forecast(fdm(fr.mort))
plot(france.fcast)
plot(france.fcast,"c")
plot(france.fcast,"v")

Plot life expectancy from lifetable

Description

plots life expectancy for each age and each year as functional time series.

Usage

## S3 method for class 'lifetable'
plot(
  x,
  years = x$year,
  main,
  xlab = "Age",
  ylab = "Expected number of years left",
  ...
)

## S3 method for class 'lifetable'
lines(x, years = x$year, ...)

Arguments

x

Output from lifetable.

years

Years to plot. Default: all available years.

main

Main title.

xlab

Label for x-axis.

ylab

Label for y-axis.

...

Additional arguments passed to plot.fds.

Author(s)

Rob J Hyndman

See Also

life.expectancy, lifetable.

Examples

france.lt <- lifetable(fr.mort)
plot(france.lt)

france.LC <- lca(fr.mort)
france.fcast <- forecast(france.LC)
france.lt.f <- lifetable(france.fcast)
plot(france.lt.f,years=2010)

Population simulation

Description

Simulate future sample paths of a population using functional models for mortality, fertility and migration.

Usage

pop.sim(
  mort,
  fert = NULL,
  mig = NULL,
  firstyearpop,
  N = 100,
  mfratio = 1.05,
  bootstrap = FALSE
)

Arguments

mort

Forecasts of class fmforecast2 for mortality.

fert

Forecasts of class fmforecast for female fertility.

mig

Forecasts of class fmforecast2 for net migration.

firstyearpop

Population for first year of simulation.

N

Number of sample paths to simulate.

mfratio

Male-female ratio used in distributing births.

bootstrap

If TRUE, simulation uses resampled errors rather than normally distributed errors.

Value

A list of two arrays containing male and female future simulated population values. The arrays are of dimension (p,h,N) where p is the number of age groups, h is the forecast horizon and N is the number of simulated sample paths.

Author(s)

Rob J Hyndman

See Also

simulate.fmforecast, simulate.fmforecast2.

Examples

## Not run: 
require(addb)
# Construct data objects
mort.sm <- smooth.demogdata(set.upperage(extract.years(australia,1950:2002),100))
fert.sm <- smooth.demogdata(extract.years(aus.fertility,1950:2002))
aus.mig <- netmigration(set.upperage(australia,100),aus.fertility,mfratio=1.0545)
# Fit models
mort.fit <- coherentfdm(mort.sm)
fert.fit <- fdm(fert.sm)
mig.fit <- coherentfdm(aus.mig)
# Produce forecasts
mort.fcast <- forecast(mort.fit)
fert.fcast <- forecast(fert.fit)
mig.fcast <- forecast(mig.fit)
# Simulate
aus.sim <- pop.sim(mort.fcast,fert.fcast,mig.fcast,australia)
## End(Not run)

Read demographic data and construct demogdata object

Description

Read data from text files and construct a demogdata object suitable for plotting using plot.demogdata and fitting an LC or BMS model using lca or an FDA model using fdm.

Usage

read.demogdata(
  file,
  popfile,
  type,
  label,
  max.mx = 10,
  skip = 2,
  popskip = skip,
  lambda,
  scale = 1
)

Arguments

file

Filename containing demographic rates.

popfile

Filename containing population numbers.

type

Character string showing type of demographic series: either “mortality”, “fertility” or “migration”.

label

Name of area from which the data are taken.

max.mx

Maximum allowable value for demographic rate. All values greater than max.mx will be set to max.mx.

skip

Number of lines to skip at the start of file.

popskip

Number of lines to skip at the start of popfile.

lambda

Box-Cox transformation parameter to be used in modelling and plotting. If missing, default values are 0 (for mortality), 0.4 (for fertility) and 1 (for migration).

scale

Number of people in the rate definition. scale=1 indicates the rates are per person; scale=1000 indicates the rates are per 1000 people.

Details

All data are assumed to be tab-delimited text files with the first column containing the year of observation and the second column containing the age level. All remaining columns are assumed to be demographic rates for sections of the population. The first row of the text file is assumed to contain the names of each column. Population data are assumed to have the same format but with population numbers in place of rates. The columns names in the two files should be identical. Note that this format is what is used by the Human Mortality Database http://www.mortality.org. If popfile contains the Exposures and file contains the Mx rates from the HMD, then everything will work seamlessly.

Value

Object of class “demogdata” with the following components:

year

Vector of years

age

Vector of ages

rate

A list containing one or more rate matrices with one age group per row and one column per year.

pop

A list of the same form as rate but containing population numbers instead of demographic rates.

type

Type of object: “mortality”, “fertility” or “migration”.

label

label

Author(s)

Rob J Hyndman

See Also

demogdata

Examples

## Not run:  norway <- read.demogdata("Mx_1x1.txt",
  "Exposures_1x1.txt", type="mortality", label="Norway")
## End(Not run)

Compute residuals and fitted values from functional demographic model or Lee-Carter model

Description

After fitting a Lee-Carter model or functional demographic model, it is useful to inspect the residuals or plot the fitted values. These functions extract the relevant information from the fit object.

Usage

## S3 method for class 'fdm'
residuals(object, ...)

## S3 method for class 'fdm'
fitted(object, ...)

## S3 method for class 'lca'
fitted(object, ...)

## S3 method for class 'lca'
residuals(object, ...)

Arguments

object

Output from fdm or lca.

...

Other arguments.

Value

residuals.fdm and residuals.lca produce an object of class “fmres” containing the residuals from the model. fitted.fdm and fitted.lca produce an object of class “fts” containing the fitted values from the model.

Author(s)

Rob J Hyndman.

See Also

fdm, lca, bms

Examples

fit1 <- lca(fr.mort)
  plot(residuals(fit1))
  plot(fitted(fit1))

Combine the upperages of a demogdata object.

Description

Computes demographic rates by combining age groups.

Usage

set.upperage(data, max.age)

Arguments

data

Demogdata object such as created using read.demogdata or smooth.demogdata.

max.age

Upper age group. Ages beyond this are combined into the upper age group.

Value

Demogdata object with same components as data but with a subset of ages.

Author(s)

Rob J Hyndman

Examples

france.short <- set.upperage(fr.mort, 85)

Compute sex ratios from mortality rates

Description

Calculates the Male/Female ratios from historical or forecasted mortality rates.

Usage

sex.ratio(data)

Arguments

data

Demogdata object of type “mortality” such as obtained from read.demogdata, or an object of class fmforecast such as the output from forecast.fdm or forecast.lca.

Value

Functional time series of sex ratios.

Author(s)

Rob J Hyndman

Examples

plot(sex.ratio(fr.mort),ylab="Sex ratios (M/F)")

Simulate future sample paths from functional demographic model forecasts.

Description

This function will simulate future sample paths given forecasting models from a functional demographic model such as those obtained using forecast.fdm or forecast.fdmpr.

Usage

## S3 method for class 'fmforecast'
simulate(
  object,
  nsim = 100,
  seed = NULL,
  bootstrap = FALSE,
  adjust.modelvar = TRUE,
  ...
)

## S3 method for class 'fmforecast2'
simulate(object, ...)

Arguments

object

Object of class fmforecast. Typically, this is output from forecast.fdm.

nsim

Number of sample paths to simulate.

seed

Either NULL or an integer that will be used in a call to set.seed before simulating the time seriers. The default, NULL will not change the random generator state.

bootstrap

If TRUE, simulation uses resampled errors rather than normally distributed errors.

adjust.modelvar

If TRUE, will adjust the model variance by the ratio of the empirical and theoretical variances for one-step forecasts.

...

Other arguments passed to simulate.fmforecast.

Value

An array containing the future simulated values (in the case of a fmforecast object), or a list of arrays containing the future simulated values (in the case of a fmforecast2 object).

Author(s)

Rob J Hyndman

See Also

forecast.fdm, forecast.lca, forecast.ftsm.

Examples

## Not run: 
france.fit <- fdm(fr.mort,order=2)
france.fcast <- forecast(france.fit,50,method="ets")
france.sim <- simulate(france.fcast,nsim=100)

france.fit2 <- coherentfdm(fr.sm)
france.fcast2 <- forecast(france.fit2,50)
france.sim2 <- simulate(france.fcast2,nsim=100)
## End(Not run)

Create smooth demogdata functions

Description

Smooth demogdata data using one of four methods depending on the value of method

Usage

smooth.demogdata(
  data,
  method = switch(data$type, mortality = "mspline", fertility = "cspline", migration =
    "loess"),
  age.grid,
  power = switch(data$type, mortality = 0.4, fertility = 1, migration = 1),
  b = 65,
  k = 30,
  span = 0.2,
  lambda = 1e-10,
  interpolate = FALSE,
  weight = data$type != "migration",
  obs.var = "empirical"
)

Arguments

data

Demogdata object such as created using read.demogdata.

method

Method of smoothing. Possibilities: "mspline" (monotonic regression splines), "cspline" (concave regression splines), "spline" (unconstrained regression splines), "loess" (local quadratic using loess).

age.grid

Ages to use for smoothed curves. Default is single years over a slightly greater range than the unsmoothed data.

power

Power transformation for age variable before smoothing. Default is 0.4 for mortality data and 1 (no transformation) for fertility or migration data.

b

Lower age for monotonicity if method=="mspline". Above this, the smooth curve is assumed to be monotonically increasing.

k

Number of knots to use for penalized regression spline estimate. Ignored if method=="loess".

span

Span for loess smooth if method=="loess".

lambda

Penalty for constrained regression spline if method=="cspline".

interpolate

If interpolate==TRUE, a linear interpolation is used instead of smoothing.

weight

If TRUE, uses weighted smoothing.

obs.var

Method for computing observational variance. Possible values: “empirical” or “theoretical”.

Details

The value of method determines the type of smoothing used.

method="mspline"

Weighted penalized regression splines with a monotonicity constraint. The curves are monotonically increasing for age greater than b. Smoothness controlled by k. Methodology based on Wood (1994). Code calls gam for the basic computations.

method="cspline"

Weighted regression B-splines with a concavity constraint. Smoothness controlled by lambda. Methodology based on He and Ng (1999). Code calls cobs for the basic computations.

method="spline"

Unconstrained weighted penalized regression splines. Equivalent to "mspline" but with b=Inf.

method="loess"

Weighted locally quadratic regression. Smoothness controlled by span. Code calls loess for the basic computations.

Value

Demogdata object identical to data except all rate matrices are replaced with smooth versions and pop matrices are replaced with disaggregated population estimates obtained using monotonic spline interpolation applied to the cumulative population data. Weight matrices are also added to the object showing the inverse variances of the estimated smooth curves.

Author(s)

Rob J Hyndman

Examples

france.sm <- smooth.demogdata(extract.years(fr.mort,1980:1997))
plot(france.sm)
plot(fr.mort,years=1980,type="p",pch=1)
lines(france.sm,years=1980,col=2)

Summary for functional demographic model or Lee-Carter model

Description

Summarizes a basis function model fitted to age-specific demographic rate data. It returns various measures of goodness-of-fit.

Usage

## S3 method for class 'fdm'
summary(object, ...)

## S3 method for class 'lca'
summary(object, ...)

Arguments

object

Output from fdm or lca.

...

Other arguments.

Author(s)

Rob J Hyndman

See Also

fdm, lca, bms, compare.demogdata

Examples

fit1 <- lca(fr.mort)
fit2 <- bms(fr.mort,breakmethod="bai")
fit3 <- fdm(fr.mort)
summary(fit1)
summary(fit2)
summary(fit3)

Compute total fertility rate from fertility rates

Description

Compute total fertility rates from age-specific fertility rates contained in a demogdata object.

Usage

tfr(data, PI = FALSE, nsim = 500, ...)

Arguments

data

Demogdata object of type "fertility" such as obtained from read.demogdata, forecast.fdm.

PI

If TRUE, produce a prediction interval.

nsim

Number of simulations to use when computing a prediction interval.

...

Other arguments passed to simulate when producing prediction intervals.

Value

If data are of class demogdata, the function returns a time series of fertility rates. If data are from forecast.fdm, the function returns an object of class forecast containing point forecasts and (optionally) prediction intervals.

Author(s)

Rob J Hyndman

See Also

fdm

Examples

plot(tfr(aus.fert))
ausfert.fcast <- forecast(fdm(aus.fert))
plot(tfr(ausfert.fcast,PI=TRUE,nsim=400))

Updating functional demographic models and coherent functional demographic models.

Description

update.fmforecast() updates fdm forecasts. The argument object is the output from forecast.fdm which has been subsequently modified with new coefficient forecasts. These new forecasts are used when re-calculating the forecast of the mortality or fertility rates, or net migration numbers. update.fmforecast2() updates fdmpr forecasts. The argument object is the output from forecast.fdmpr which has been subsequently modified with new coefficient forecasts.

Usage

## S3 method for class 'fmforecast'
update(object, ...)

## S3 method for class 'fmforecast2'
update(object, ...)

Arguments

object

Output from either fdm or coherentfdm.

...

Extra arguments currently ignored.

Value

A list of the same class as object.

Author(s)

Rob J Hyndman.

See Also

forecast.fdm, forecast.fdmpr

Examples

## Not run: 
france.fit <- fdm(fr.mort,order=2)
france.fcast <- forecast(france.fit,50)
# Replace first coefficient model with ARIMA(0,1,2)+drift
france.fcast$coeff[[2]] <- forecast(Arima(france.fit$coeff[,2],
                                          order=c(0,1,2), include.drift=TRUE), h=50, level=80)
france.fcast <- update(france.fcast)

fr.short <- extract.years(fr.sm,1950:2006)
fr.fit <- coherentfdm(fr.short)
fr.fcast <- forecast(fr.fit)
par(mfrow=c(1,2))
plot(fr.fcast$male)
# Replace first coefficient model in product component with a damped ETS model:
fr.fcast$product$coeff[[2]] <- forecast(ets(fr.fit$product$coeff[,2], damped=TRUE),
                                        h=50, level=80)
fr.fcast <- update(fr.fcast)
plot(fr.fcast$male)

## End(Not run)