triangle.test: Make a Triangle test for a set of products In SensoMineR: Sensory data analysis with R

Description

Make a Triangle test for a set of products.

Usage

 `1` ```triangle.test (design, answer, preference = NULL) ```

Arguments

 `design` a data.frame corresponding to the design use to make the Triangle test (typically the ouput of the function `triangle.design` `answer` a vector of the answers of all the panelists; all the answer should be "X", "Y" or "Z" `preference` a vector of the preference of the panelists; all the answer should be "X", "Y" or "Z" (by default, there preference are not taken into account)

Details

Triangle test: panelists receive three coded samples. They are told that two of the sample are the same and one is different. Panelists are asked to identify the odd sample.

Value

Returns a list of matrices. Each matrix give the reult for all the pair of products:

 `nb.comp` a matrix with the number of comparisons done for each pair of products; `nb.ident` a matrix with the number of panelists who indicate the odd product for each pair of products; `p.value` a matrix with the p-value of the Triangle tests for each pair of products; `nb.recognition` estimation of the panelists who really perceived the difference between two product, for each pair of product; `maxML` Maximum Likelihood of the estimation of the number of panelists who really perceive the difference between the products; `confusion` estimation of the percentage of panelists who do not perceived the difference between two product, for each pair of product; `minimum` minimum of panelists who should detect the odd product to can say that panelists perceive the difference between the products, for each pair of products; `preference` number of times that product of row i is prefered that product in column j for the panelists who find the odd product.

Author(s)

Fran<e7>ois Husson

`triangle.pair.test`, `triangle.design`

Examples

 ```1 2 3 4``` ```design = triangle.design(nbprod = 4, nbpanelist = 6, bypanelist = 3) answer = c("X","Y","Y","X","Z","X","Y","X","Z", "X","X","Z","X","Y","X","Z","X","Y") triangle.test (design, answer) ```

Example output

```Loading required package: FactoMineR
\$nb.comp
1 2 3 4
1 0 3 3 3
2 3 0 3 3
3 3 3 0 3
4 3 3 3 0

\$nb.ident
1 2 3 4
1 0 0 1 3
2 0 0 0 2
3 1 0 0 1
4 3 2 1 0

\$p.value
1         2         3          4
1 1.00000000 1.0000000 0.7037037 0.03703704
2 1.00000000 1.0000000 1.0000000 0.25925926
3 0.70370370 1.0000000 1.0000000 0.70370370
4 0.03703704 0.2592593 0.7037037 1.00000000

\$nb.recognition
1 2 3 4
1 0 0 0 2
2 0 0 0 1
3 0 0 0 0
4 2 1 0 0

\$maxML
1         2         3         4
1 1.0000000 0.0000000 0.4444444 1.0000000
2 0.0000000 1.0000000 0.0000000 0.6666667
3 0.4444444 0.0000000 1.0000000 0.4444444
4 1.0000000 0.6666667 0.4444444 1.0000000

\$confusion
1         2 3         4
1 1.0000000 1.0000000 1 0.3333333
2 1.0000000 1.0000000 1 0.6666667
3 1.0000000 1.0000000 1 1.0000000
4 0.3333333 0.6666667 1 1.0000000

\$minimum
1  2  3  4
1 NA  3  3  3
2  3 NA  3  3
3  3  3 NA  3
4  3  3  3 NA
```

SensoMineR documentation built on May 31, 2017, 4:23 a.m.