smerc_cluster: Prepare `smerc_cluster`

Description

smerc_cluster prepares a smerc_cluster.

Usage

smerc_cluster(
  tobs,
  zones,
  pvalue,
  coords,
  cases,
  pop,
  ex,
  longlat,
  method,
  rel_param,
  alpha,
  w = NULL,
  d = NULL,
  a = NULL,
  shape_all = NULL,
  angle_all = NULL,
  weights = NULL
)

Value

A smerc_cluster object. The object generally has the following components:

clusters: A list containing information about the significant clusters. See further details below.
coords: The matrix of centroid coordinates.
number_of_regions: The number of regions considered.
total_population: The total population in the regions.
total_cases: The total number of cases in the regions.
cases_per_100k: The rate of cases per 100,000 persons.
method: The name of the method applied.
rel_param: A list of relevant method parameters.
alpha: The significance level.
longlat: A logical value indicating which type of distance was used.

Each element of the clusters component has:

locids: The ids of the regions in the cluster.
centroid: The cluster centroid.
r: The radius of the region (from the starting region to last region of the cluster).
max_dist: The maximum intercentroid distance between all the regions in the cluster.
population: The total population in the cluster.
cases: The number of cases in the cluster.
expected: The expected number of cases in the cluster.
smr: Standardized mortality ratio (cases/expected) in the cluster.
rr: Relative risk in the cluster window. This is (cases/pop)/((total_cases - cases)/ (total_population - population)).
loglikrat: The log of the likelihood ratio test statistic for the cluster. Only valid for the scan-type tests.
test_statistic: The test statistic for the cluster.
pvalue: The p-value of the test statistic associated with the cluster.
w: The adjacency information for the cluster.

For elliptic.test, clusters

additionally has:

semiminor_axis: The semi-minor axis length for the ellipse.
semimajor_axis: The semi-major axis length for the ellipse.
angle: The rotation angle of the ellipse.
shape: The shape of the ellipse.

Arguments

tobs: The vector of observed test statistics for each zone
zones: A list of zones
pvalue: The p-value associated with each test statistic
coords: An \(n \times 2\) matrix of centroid coordinates for the regions in the form (x, y) or (longitude, latitude) is using great circle distance.
cases: The number of cases observed in each region.
pop: The population size associated with each region.
ex: The expected number of cases for each region. The default is calculated under the constant risk hypothesis.
longlat: The default is FALSE, which specifies that Euclidean distance should be used. If longlat is TRUE, then the great circle distance is used to calculate the intercentroid distance.
method: A character string indicating the method used to construct the smerc_cluster.
rel_param: A names list with the relevant parameters associated with method.
alpha: The significance level of the test.
w: A binary spatial adjacency matrix for the regions.
d: A precomputed distance matrix based on coords
a: A single value >= 0 indicating the penalty to use for elliptic.test.
shape_all: A vector of shape parameters associated with zones.
angle_all: A vector of angle parameter associated with zones.
weights: A vector of weights that multiply the cases, ex, and pop prior to computing summary statistics.