This help file describes the distributions used for data creation in
`simstudy`

.

## Arguments

formula |
Desired mean as a Number or an R expression for mean as a
String. Variables defined via `defData()` and variables within the
parent environment (prefixed with `..` ) can be used within the formula.
Functions from the parent environment can be used without a prefix. |

variance |
Number. Default is `0` . |

link |
String identifying the link function to be used. Default is
`identity` . |

## Details

For details about the statistical distributions please see
stats::distributions, any non-statistical distributions will be
explained below. Required variables and expected pattern for each
distribution can be found in this table:

**name** | **formula** | **format** | **variance** | **link** |

beta | mean | String or Number | dispersion value | identity or logit |

binary | probability for 1 | String or Number | NA | identity or logit |

binomial | probability of success | String or Number | number of trials | identity or logit |

categorical | probabilities | `p_1;p_2;..;p_n` | NA | NA |

exponential | mean (lambda) | String or Number | NA | identity or log |

gamma | mean | String or Number | dispersion value | identity or log |

mixture | formula | `x_1 ` |`p_1 + x_2` |`p_2 ... x_n` |` p_n` | NA | NA |

negBinomial | mean | String or Number | dispersion value | identity or log |

nonrandom | formula | String or Number | NA | NA |

normal | mean | String or Number | variance | NA |

noZeroPoisson | mean | String or Number | NA | identity or log |

poisson | mean | String or Number | NA | identity or log |

uniform | range | `from;to` | NA | NA |

uniformInt | range | `from;to` | NA | NA |

## Mixture

The mixture distribution makes it possible to mix to
previously defined distributions/variables. Each variable that should be
part of the new distribution `x_1,...,X_n`

is assigned a probability
`p_1,...,p_n`

. For more information see
rdatagen.net.

## Examples

#> varname formula variance dist link
#> 1: external 3 + log(..ext_var) 0.5 normal identity

#> id external
#> 1: 1 4.864108
#> 2: 2 3.665887
#> 3: 3 5.448120
#> 4: 4 3.531613
#> 5: 5 5.689579