From: Taka Matzmoto <sell_mirage_ne_at_hotmail.com>

Date: Wed 01 Feb 2006 - 13:03:25 EST

R-help@stat.math.ethz.ch mailing list

https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Wed Feb 01 13:14:37 2006

Date: Wed 01 Feb 2006 - 13:03:25 EST

Hi R users

I have a simple data for calculating goodness-of-fit statistics (e.g., X2 by Pearson, G2 by Wilks)

*#################################################
*

observed<-c(424,174,0,402)

expected<-c(282.7174, 314.2972, 142.3142, 260.6712)
2*sum(observed*log(observed/expected)) # for X2
sum((observed-expected)^2/expected) # for G2

*#################################################
*

(note. expected ones were calculating by a model I used, not by marginal of observed ones.)

The third element of the observed vector is zero.

For third element, 0 * log(0/142.3142) is NaN. That is why I got NaN for G2.

I think 0 multiplied by anything should be zero. Am I wrong ?

Is there any R functions to correct zero cells for calculating G2? If there is, I like to know some

references justifying the correction.

Thank you in advance

TM

R-help@stat.math.ethz.ch mailing list

https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Wed Feb 01 13:14:37 2006

*
This archive was generated by hypermail 2.1.8
: Fri 03 Mar 2006 - 03:42:16 EST
*