surveillance (version 1.2-1)

create.disProg: Creating an object of class disProg

Description

Creates an object of class disProg from a vector with the weeknumber (week) and matrices with the observed number of counts (observed) and the respective state chains (state), where each column represents an individual time series. The matrices neighbourhood and populationFrac provide information about neighbouring units and population proportions.

Usage

create.disProg(week, observed, state, start=c(2001,1), freq=52, 
  neighbourhood=NULL, populationFrac=NULL, epochAsDate=FALSE)

Arguments

week

index in the matrix of observations, typically weeks

observed

matrix with parallel time series of counts where rows are time points and columns are the individual time series for unit/area $i, i=1,\ldots,m$

state

matrix with corresponding states

start

vector of length two denoting the year and the sample number (week, month, etc.) of the first observation

freq

sampling frequency per year, i.e. 52 for weekly data, 12 for monthly data, 13 if 52 weeks are aggregated into 4 week blocks.

neighbourhood

neighbourhood matrix $N$ of dimension $m \times m$ with elements $n_{ij}=1$ if units $i$ and $j$ are adjacent and 0 otherwise

populationFrac

matrix with corresponding population proportions

epochAsDate

interpret the integers in week as Dates. Default is FALSE

Value

• disProg
  object of class disProg

encoding

latin1

Examples

# create an univariate disProg object for the salmonella.agona data
  data(salmonella.agona)
  week <- 1:length(salmonella.agona$observed)
  salmonellaDisProg <- create.disProg(week=week, observed=salmonella.agona$observed,
  state=salmonella.agona$state)
  
  # plot salmonella cases
  title <- "Salmonella Agona cases in the UK"
  plot(salmonellaDisProg, title = title, xaxis.years=TRUE, legend.opts=NULL,
        startyear = 1990, firstweek = 1)