[R] npmc problem?

[Etsushi Kato]

Hi,

I recently tried to conduct non-parametric multiple comparison with 
npmc package, and encountered some problem; sometimes it stopped with 
following error.

Error in uniroot(f = function(arg) p - z.dist(arg, corr = corr, df = 
df,  :
         f() values at end points not of opposite sign


Although I'm not quite sure about calculation of z.quaintile in npmc.R, 
it seems increment of upper (or decrement of lower) is not sufficient 
since the z.dist() value is not repeatable (randomized values) resulted 
from mvtnorm, and sometimes failed to do uniroot().

For my case, I can avoid the error with changing upper and lower with 
adding or subtracting 2 for uniroot.    Is it safe to use such modified 
verson of npmc?

--- npmc.orig   2004-04-26 14:13:00.000000000 +0900
+++ npmc        2004-04-26 16:50:59.000000000 +0900
@@ -131,7 +131,7 @@
          lower <- lower-1;
      }
      ur <- uniroot(f=function(arg) 
p-z.dist(arg,corr=corr,df=df,sides=sides),
-                  upper=upper, lower=lower
+                  upper=upper+2, lower=lower-2
                    );
      ur$root;
    }

Here is the my test dataframe.

"class" "var"
"1"  1197.90816
"1"  3725.82418
"1"  1159.66667
"1"  2835.05556
"1"  2093.20000
"2"  3012.50000
"2"  1895.52381
"2"  3033.07692
"2"  1790.00000
"2"  4103.60000
"2"  1870.13636
"2"  3331.15385
"2"  2066.00000
"2"  2021.92308
"3"  2440.05000
"3"  4615.78893
"3"  2063.50000
"3"  1193.65790
"4"  1569.62500
"4"  1912.72222
"4"  4708.72727
"4"  1722.95833
"4"  2809.14286
"5"  1077.43478
"5"   193.77500
"5"  1230.23529
"5"  8180.73171
"5"  3879.00000
"5"  1050.55556
"6"  1406.72000
"6"   208.94737
"6"  1276.68421
"6"   639.85714
"6"   793.73684
"6"  1043.83871
"8"   647.55000
"8"    97.81000
"8"   208.67308
"8"   765.85000
"8"  2803.00000
"8"   543.71429
"8"   120.16000
"8"  5757.25000
"8"  5211.62500
"9"  3675.00000
"9"   479.09508
"9"  2620.70707
"9"  3095.75000
"9"   633.16250
"10"  2397.03390
"10"   524.37625
"10"  2693.09524
"10"   796.36250
"10"  2261.87500
"10"  1122.01250
"11"  1543.10000
"11"  2127.04545
"11"  1692.87500
"12"  2752.75000
"12"   385.43750
"12"  4576.50000
"12"  7006.12500
"12"  2779.87500
"12"  2704.25000
"13"  3715.25000
"13"  3447.87500
"13"   509.60000
"13"  3238.62500
"13"   674.06250
"13"  4329.62500
"13"  5593.50000
"14"  2666.87500
"14"  1636.37500
"14"   195.76250
"14"   687.06250
"14"  2175.50000
"14"  1385.87500
"15"   571.41250
"15"  2457.89812
"15"  4110.75935
"16"  3279.87500
"16"  2788.50000
"16"   641.95000
"16"   431.38280
"16"  1343.25000
"16"  1952.62500
"17"  2917.00000
"17" 14622.54902
"17"  5030.37500
"19"  1118.98750
"19"   609.13750
"19"  1580.37500
"19"   770.58750
"19"    53.66231
"19"   253.28750
-- 
Etsushi Kato
ekato at ees.hokudai.ac.jp