discrimPwr {sensR}R Documentation

Sensory discrimination power analysis

Description

Computes the power of the hypothesis test of no sensory difference for any one of four methods: 2-AFC, 3-AFC, duotrio and triangle tests given the underlying sensory difference delta, the type I test level and the sample size.

Usage

discrimPwr(delta, sample.size, alpha = .05,
           method = c("duotrio", "threeAFC", "twoAFC", "triangle")) 

Arguments

delta The underlying sensory difference (non-negative)
sample.size The sample size (a positive integer)
alpha The type I level of the test (must be between zero and one)
method The discrimination test protocol. Four allowed values: "twoAFC", "threeAFC", "duotrio", "triangle"

Details

The function uses one of the dedicated binomial families.

Value

The power.

Author(s)

Rune Haubo B Christensen and Per Bruun Brockhoff

References

Brockhoff, P.B. and Christensen, R.H.B (2008). Thurstonian models for sensory discrimination tests as generalized linear models. Manuscript for Food Quality and Preference.

See Also

triangle, twoAFC, threeAFC, duotrio, discrim, discrimSim, AnotA, discrimSS, samediff, findcr

Examples

## Finding the power of a discrimination test with a sensory delta of 1,
## a sample of size 30 and a type I level of .05:
discrimPwr(1, 30, 0.05, "twoAFC")
discrimPwr(1, 30, 0.05, "threeAFC")
discrimPwr(1, 30, 0.05, "duotrio")
discrimPwr(1, 30, 0.05, "triangle")

[Package sensR version 1.0.0 Index]