[R] Summarizing levels for future commands

[Suzanne E. Blatt]

Hello again,

Figured out one of my errors, forgot the 's' on the 'names' command.  So, now I can get my max (or min) of the levels within my table and I can plug them successfully into my function farther along my code.  However, how can I get the 2nd or 3rd most frequent level and use them as well as the most frequent level?

Thanks for the continued help,

Suzanne


Douglas Bates <bates at stat.wisc.edu> wrote:

>SuzieBlatt at netscape.net (Suzanne E. Blatt) writes:
>
>> Hi.  This will hopefully be readily understood but if not, bear with me.
>> 
>> I have to do a repeated analysis (in spatstat) and want to batch file it.  For each of my 'runs' certain variables change.  At present I am manually specifying these changes and want to automate it if possible.
>> 
>> Ok, I am creating an object which is comprised of 'levels' that are 'characters'.  Further in my program I need to select one of these 'levels' as the comparison to the others.  The one I want to select is the most frequent and then compare it to the second most frequent.  Is there anyway to get R to determine the most frequency of 'levels' in an object and then use a specific one in future functions?  I couldn't find it in my search through the manual or the r-help archives.
>> 
>> I hope what I am attempting to do is clear, let me know if it isn't.
>
>I think I know what you want to do but I'm not sure.  I believe you
>want to find the mode, or the "most popular" level.  For example, in
>the following sample of size 50 from the values 1:10
>
>> samp = sample(1:10, 50, replace = TRUE)
>> table(samp)
>samp
> 1  2  3  4  5  6  7  8  9 10 
> 5  3  7  3  4  2  8  9  3  6 
>
>the most popular value is 8.
>
>As you can see, the table function tells you the frequencies of the
>values.  From that it is just a matter of extracting the index of the
>value with the maximum count and getting the label.
>
>> names(tbl)[match(max(tbl), tbl)]
>[1] "8"
>
>Hope this helps.
>