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

Description Usage Arguments Details Value Author(s) See Also Examples

Make a Triangle test for a set of products.

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

`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)

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.

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.

Fran<e7>ois Husson

triangle.pair.test, triangle.design

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)

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