# A function to calculate the likelihood ratio

### Description

This function calculates the likelihood ratio for an allele causing a disease asssuming that the allele is extremely rare so that all family members who have the allele got it directly from a common ancestor in the pedigree.

### Usage

1 | ```
calculate.likelihood.ratio(ped, affected.boolean)
``` |

### Arguments

`ped` |
A dataframe of a pedigree containing id, momid, dadid, age(Current age or age affected), y.born(year born), female(a logical where 1 is female and 0 is male), and genotype(0 is non-carrier, 1 carrier, and 2 unknown) in any order but with these specific column names. |

`affected.boolean` |
A boolean(or logical) vector where 0 is unaffected and 1 is affected. |

### Value

`likelihood.ratio ` |
The resultant likelihood ratio |

`separating.meioses ` |
The number of meioses separating all individuals known to have the genotype including those that are are indirectly known to have the genotype. |

`number.genotypes.found ` |
The number of permissible genotypes found for the pedigree. |

### Author(s)

John Michael O. Ranola and Brian H. Shirts

### Examples

1 2 3 | ```
##---- Should be DIRECTLY executable !! ----
##-- ==> Define data, use random,
##-- or do help(data=index) for the standard data sets.
``` |