[R] Summary shows wrong maximum

[rolf at math.unb.ca]

Brian Ripley wrote:

> 'Unfortunately' you give no credentials for your ex cathedra
> pronouncement.  E.g.
> 
> http://en.wikipedia.org/wiki/Significant_digits
> 
> says
> 
> The situation regarding trailing zero digits that fall to the left of
> the decimal place in a number with no digits provided that fall to
> the right of the decimal place is less clear, but these are typically
> not considered significant unless the decimal point is placed at the
> end of the number to indicate otherwise (e.g., "2000." versus
> "2000"). To make things more clear, trailing zeros are only
> recognized as significant figures if the number they are a part of
> has a decimal point. For example, 450 only has two sig figs, but 450.
> has three.
> 
> which directly contradicts you.  So this is at best a matter of
> opinion, and credentials do matter for opinions.

	In the elementary statistics text ``Statistics for the Life
	Sciences'' (Samuels and Witmer, Prentice-Hall, 3rd ed.;
	fairly respectable credentials)  there is an appendix on
	Significant Digits which says, amongst other things:

	``How many significant digits are in the number 23000?
	When the number is expressed in this way --- in ordinary
	rather than scientific notation --- it is not really
	possible to tell how many significant digits it has.''

	....

	``Scientific notation removes the ambiguity.''

	Determining the significance of digits from the presence
	of a decimal point is perhaps a ``reasonable'' convention,
	but it is certainly not one that is widely practiced or
	understood.  Relying on an obscure convention is fraught
	with risk.

					cheers,

						Rolf Turner
						rolf at math.unb.ca