Dear Rui, 1) With test subject I mean each file (I have posted three similar files above (2, 50 and 1112), but each test subject has one exact file (which differs of course! --> 2, 50 an 1112 are the same file but I renamed it for the problem described ans solved above). In this file the vpNum is always the same (for each test subject of course; example: for test subject 44 it is always vpNum = 44). The examples above (2, 50 and 1112) are in fact all the second test subject's file (vpNum always "2").
2) With "trials" or "trialCount" I mean the number of trials (149 in your example, and 151 in the examples 2, 50 and 1112). But the number of trials differs between subjects, because in the examples below (vpNum = 3, 43 and 63) it is 152 (for vpNum = 3), 150 (for vpNum = 43) and 157 (for vpNum = 63). http://r.789695.n4.nabble.com/file/n4636074/Fluencyflanker_3.txt Fluencyflanker_3.txt http://r.789695.n4.nabble.com/file/n4636074/Fluencyflanker_43.txt Fluencyflanker_43.txt http://r.789695.n4.nabble.com/file/n4636074/Fluencyflanker_63.txt Fluencyflanker_63.txt 3) I mean the number of correct answers given per test subject (for example for test subject 3 in the previous example (5 rows above) we have 152 trials and 4 trials that are not correct, which means 148 correct trials (with the categorical value "1")). So in R this would be the ratio of: > 148/152 [1] 0.9736842 The wanted output should (if possible) look like this (here only for vpNum = 3 !!!): vpNum trial OR trialCount correct (reactions) ratio (which means: number correct / trialCount) 3 152 148 0.9736842 The final output should look like this: vpNum trial OR trialCount correct (reactions) ratio (which means: number correct / trialCount) 1 n n x 2 n n x 3 152 148 0.9736842 and so on until vpNum = 65 (In my question before I forgot to ask for the column "vpNum", sorry about that!). I hope this makes it more clear! Thanks for your time and help! Kind regards -- View this message in context: http://r.789695.n4.nabble.com/Extracting-arithmetic-mean-for-specific-values-from-multiple-txt-files-tp4635809p4636074.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
