rgr (version 1.1.15)

gx.hypergeom: Compute Probabilities for Target Recognition

Description

The hypergeometric distribution is used to infer if the number of anomalous sites along a traverse reliably reflect the presence of the dispersion pattern from a known mineral occurrence. The function displays the probability of the observed outcome could be due to chance alone.

Usage

gx.hypergeom(tt, aa, kk, xx)

Arguments

tt

total number of sites along a traverse.

aa

number of sites that a priori should be anomalous.

kk

total number of > threshold sites.

xx

number of the aa that are > threshold.

Details

See Stanley (2003) for details, the examples below reproduce the results in Table 1 and Table 2.

References

Stanley, C.R., 2003. Statistical evaluation of anomaly recognition performance. Geochemistry: Exploration, Environment, Analaysis, 3(1):3-12.

See Also

gx.runs

Examples

# NOT RUN {
## From Stanley (2003) Tables 1 and 2

gx.hypergeom(31, 10, 5, 3)
gx.hypergeom(31, 10, 3, 2)
gx.hypergeom(31, 10, 4, 3)

gx.hypergeom(31, 10, 4, 4)
gx.hypergeom(31, 10, 6, 5)
gx.hypergeom(31, 10, 3, 3)
# }