fast.zones {smerc} | R Documentation |
Determine sequence of fast subset scan zones
Description
fast.zones
determines the unique zones obtained by
implementing the fast subset scan method of Neill (2012).
Usage
fast.zones(cases, pop, ubpop = 0.5, simple = TRUE)
Arguments
cases |
The number of cases observed in each region. |
pop |
The population size associated with each region. |
ubpop |
The upperbound of the proportion of the total population to consider for a cluster. |
simple |
A logical value indicating whether a simple version of the fast zones should be returned. See Details. |
Details
The simple
argument determines the formatting of
the returned zones. If simple = TRUE
, then a
vector containing the sequential indices of the regions
in each successive zones is returned. If simple =
FALSE
, then the complete list of all zones is returned
(which is the standard format of most of the other
*.zones
functions.
The zones returned must have a total population less than
ubpop * sum(pop)
of all regions in the study area.
Value
Returns a vector of regions to sequentially and cumulatively consider for clustering.
Author(s)
Joshua French
References
Neill, D. B. (2012), Fast subset scan for spatial pattern detection. Journal of the Royal Statistical Society: Series B (Statistical Methodology), 74: 337-360. <doi:10.1111/j.1467-9868.2011.01014.x>
Examples
data(nydf)
cases <- nydf$cases
pop <- nydf$pop
# compare output format
fast.zones(cases, pop, ubpop = 0.05)
fast.zones(cases, pop, ubpop = 0.05, simple = FALSE)