Dear all, I would like to do t-test across two columns "name" with different "cat" with overall mean ("val").
(Removing if there is a single observation) And finally, make a matrix with t-value and p-value associated with a name (in rows) and cat (in columns) dput(x) structure(list(name = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Label = c("12.2", "15.9" ), class = "factor"), cat = structure(c(2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 3L, 1L, 3L, 3L, 3L, 3L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 7L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 6L, 5L, 6L, 6L, 6L, 6L, 6L, 6L, 6L), .Label = c("p178266580", "p178269196", "p178316310", "p191287337", "p195158904", "p196921846", "p197427158", "p238921966"), class = "factor"), val = c(148.90772, 184.253375, 183.974866666667, 191.868125, 173.30515, 187.876975, 177.453775, 184.799525, 212.39065, 205.504525, 186.152025, 194.337075, 193.2703, 204.71665, 211.4452, 202.609175, 203.72918, 193.7261, 196.1186, 202.79556, 203.48818, 191.13744, 205.23315, 198.66842, 196.81032, 200.90512, 206.13564, 205.372225, 196.22835, 211.04686, 219.977133333333, 224.7602, 231.6596, 211.105816666667, 215.44474, 210.83514, 228.173125, 224.09034, 212.96026, 239.0085, 213.5407, 227.12115, 209.24888, 232.8964, 232.22146, 228.1643, 236.43082, 232.20792, 238.49192, 224.64014, 233.75898, 207.06138, 215.3649, 211.14802, 201.86854, 200.52278, 199.05752, 194.90904, 214.44334, 249.357266666667, 239.98525, 234.508483333333, 243.865083333333, 233.595816666667, 248.1219, 225.289416666667, 248.220883333333, 193.69566, 198.43578, 205.06055, 208.525975, 198.28692, 206.88496, 201.60162, 205.7943, 210.5117, 196.69886, 193.58288, 198.86094, 201.81676, 225.8266, 205.879725, 218.370475, 214.006125, 198.74038, 206.00314, 198.37446, 225.5357, 216.721025, 226.543925, 158.1011, 158.15674, 166.07518, 179.942225, 158.16046, 165.0685, 159.56146 )), .Names = c("name", "cat", "val"), class = "data.frame", row.names = c( NA, 97L)) Thanks Nico [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.