Setting covariate grouping levels:

!FACPOINTS and !POLPOINTS

The fac() and pol() model terms need to classify a covariate into discrete classes. This is usually done on the basis of unique covariate values. However, ASReml will actually consider close points as being the same. This is controlled by

     !FACPOINTS n affects the number of distinct points recognised by the fac() model function. The default value of n is 1000 so that points closer than 0.1% of the range are regarded as the same point.

     !POLPOINTS n affects the number of distinct points recognised by the pol() model function. The default value of n is 1000 so that points closer than 0.1% of the range are regarded as the same point.

Example

One use of facpoints is in association with fac(dam,year) used to define a concise interaction of dam and year, where there are more than 1000 dams.

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