# Make a Triangle test for a set of products

### 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 |

`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

### See Also

`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)
``` |