citest-generic: Generic function for conditional independence test

In gRim: Graphical Interaction Models

Generic function for conditional independence test

Description

Generic function for conditional independence test. Specializes to specific types of data.

Usage

ciTest(x, set = NULL, ...)

Arguments

x	An object for which a test for conditional independence is to be made. See 'details' for valid types of x.
set	A specification of the test to be made. The tests are of the form u and v are independent condionally on S where u and v are variables and S is a set of variables. See 'details' for details about specification of set.
...	Additional arguments to be passed on to other methods.

Details

x can be

1. a table (an array). In this case ciTest_table is called.

2. a dataframe whose columns are numerics and factors. In this case ciTest_df is called.

3. a list with components cov and n.obs. In this case ciTest_mvn is called.

set can be

1. a vector,

2. a right-hand sided formula in which variables are separated by '+'.

In either case, it is tested if the first two variables in the set are conditionally independent given the remaining variables in set. (Notice an abuse of the '+' operator in the right-hand sided formula: The order of the variables does matter.)

Value

An object of class citest (which is a list).

Author(s)

Søren Højsgaard, [e-mail]

See Also

ciTest_table, ciTest_df, ciTest_mvn, chisq.test

Examples

## contingency table:
data(reinis)
## dataframe with only numeric variables:
data(carcass)
## dataframe with numeric variables and factors:
data(milkcomp1)

ciTest(cov.wt(carcass, method='ML'), set=~Fat11 + Meat11 + Fat12)
ciTest(reinis, set=~smo + phy + sys)
ciTest(milkcomp1, set=~tre + fat + pro)

gRim documentation built on Oct. 16, 2024, 1:07 a.m.