It's the print method that determines this.
See
stats:::print.summary.lm
and in particular the if clause beginning:
if (rdf > 5L) {
R code is open source. Once you know what to look for, you can examine
it yourself.
-- Bert
On Mon, Jan 9, 2012 at 9:25 AM, Rich Shepard <rshepard at appl-ecosys.com>
wrote:> ?All but one of the summaries of multiple linear regressions in this
> analysis set present the residuals by min, 1Q, median, 3Q, and max.
Example:
>
> lm(formula = TDS ~ Cond + Ca + Cl + Mg + Na + SO4, data = snow.cast)
> Residuals:
> ? ? Min ? ? ? 1Q ? Median ? ? ? 3Q ? ? ?Max -277.351 ?-32.551 ? -2.621
> 40.812 ?245.272
>
> The one that doesn't has only a small number of rows (23) and presents
the
> results as:
>
> lm(formula = TDS ~ Cond + Ca + Cl + Mg + SO4, data = rnchH.cast)
> Residuals:
> ? ? ?8 ? ? ? 9 ? ? ?10 ? ? ?11 ? ? ?12 ? ? ?13 ? ? ?14 ? ? ?16 ? ? ?20 ?21
> -2.1926 ?3.2306 -3.9823 -4.0491 ?0.5284 ?1.9354 ?2.4798 ?0.8952 -3.0642
> ?0.8781
> ? ? 22
> ?3.3408
>
> ?What might cause this difference?
>
> Rich
>
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> and provide commented, minimal, self-contained, reproducible code.
--
Bert Gunter
Genentech Nonclinical Biostatistics
Internal Contact Info:
Phone: 467-7374
Website:
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