tango.stat {smerc}

Tango's statistic

Description

tango.stat computes Tango's index (Tango, 1995), including both the goodness-of-fit and spatial autocorrelation components. See Waller and Gotway (2005).

Usage

tango.stat(cases, pop, w)

Arguments

cases

The number of cases observed in each region.

pop

The population size associated with each region.

w

An n \times n weights matrix.

Value

Returns a list with the test statistic (tstat), the goodness-of-fit component (gof), and the spatial autocorrelation component (sa).

Author(s)

Joshua French

References

Tango, T. (1995) A class of tests for detecting "general" and "focused" clustering of rare diseases. Statistics in Medicine. 14:2323-2334.

Waller, L.A. and Gotway, C.A. (2005). Applied Spatial Statistics for Public Health Data. Hoboken, NJ: Wiley.

Examples

data(nydf)
coords <- as.matrix(nydf[, c("longitude", "latitude")])
w <- dweights(coords, kappa = 1, type = "tango", longlat = TRUE)
tango.stat(nydf$cases, nydf$pop, w)