builtin.gams {UCS} | R Documentation |

List available GAMs (generalised association measures) that can
be computed with functions such as `gam.score`

, `add.gams`

and `gam.iso`

, or test whether a specific GAM is available.
Additional GAMs can be defined with the `register.gam`

function.

builtin.gams() is.builtin.gam(names) register.gam(name, equation, iso.equation=NULL)

`names` |
a character vector specifying the names of GAMs whose availability is tested |

`name` |
a single character string specifying the name of a GAM that is defined or re-defined |

`equation` |
a function that computes GAM scores from standard or ebo-coordinates (see below for details) |

`iso.equation` |
an optional function that computes iso-surfaces in standard or ebo-coordinates (see below for details) |

The names of built-in GAMs are identical to those of the corresponding
standard AMs (e.g. `t.score`

and `chi.squared.corr`

).

The `equation`

argument of `register.gam`

, i.e. the equation
defining a new GAM), must be a function with the signature ```
(o,
e, b, f, f1, f2, N)
```

. This function can computes GAM scores either
from the ebo-coordinates `e, b, o`

or from the standard
coordinates `f, f1, f2, N`

. It is always invoked with all seven
arguments, which are guaranteed to be vectors of the same length, and
must return a vector of corresponding GAM scores.

When an explicit equation for iso-surfaces *\{g = γ\}*
exists, it can be made available through the optional argument
`iso.equation`

, which expects a function with the signature
`(gamma, e, b, f1, f2, N)`

. Again, all six arguments are
guaranteed to be vectors of the same length, and the function must
return the corresponding *o* (or *f*) coordinates that
satisfy the condition *g(o, e, b) = γ* (or *g(f, f_1,
f_2, N) = γ*). When the `iso.equation`

function is
available for a GAM, it will be used by `gam.iso`

for greater
speed and accuracy. Otherwise, the iso surface is determined by
a binary search algorithm (which has a unique solution for any
semi-sound GAM).

The signatures of the `equation`

and `iso.equation`

functions are checked by `register.gam`

, which will abort with an
error message if they are not correct.

`builtin.gams`

returns a character vector listing the names of
available GAMs. `is.builtin.gam`

returns a logical vector
indicating which of the GAMs in the vector `names`

are available.

`builtin.ams`

, `gam.score`

,
`add.gams`

, `gam.iso`

, `gam.helpers`

print(builtin.gams()) all(is.builtin.gam(c("MI", "t.score", "chi.squared"))) register.gam("MI5", eq = function (o, e, b, f, f1, f2, N) { log10(o^5 / e) }, iso = function (gamma, e, b, f1, f2, N) { 10^(gamma/5) * e^(1/5) })

[Package *UCS* version 0.5 Index]