Keith Larson wrote on 12/28/2011 04:02:39 AM:
> Dear list,
>
> The below dataset and code creates a new dataset with the results from
> the function cor.test being performed on each individual
> ('Individual_ID') from my original dataset. How do I convert each
> variable from the cor.test results to a numeric data type, as it is
> passed into the new dataframe? For example, 'estimate', 'p.value', and
> 'conf.int' should be numeric not character. Second, I would like
> variable 'conf.int' to be two variables, 'lowlim' and 'uplim'.
>
> Many Cheers,
> Keith
>
> ## Create sample dataset
> WW_Wing_SI <-
> structure(list(Individual_ID = c("WW_08A_02", "WW_08A_02", "WW_08A_02",
> "WW_08A_02", "WW_08A_02", "WW_08A_02", "WW_08A_02", "WW_08A_02",
> "WW_08A_02", "WW_08A_03", "WW_08A_03", "WW_08A_03", "WW_08A_03",
> "WW_08A_03", "WW_08A_03", "WW_08A_03", "WW_08A_03", "WW_08A_03"
> ), FeatherPosition = c(1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 3, 4,
> 5, 6, 7, 8, 9), Delta13C = c(-18.67, -19.16, -20.38, -20.96,
> -21.61, -21.65, -21.31, -20.8, -21.28, -20.06, -20.3, -21.21,
> -22.9, -22.87, -21.13, -20.68, -20.58, -20.69)), .Names =
c("Individual_ID",
> "FeatherPosition", "Delta13C"), row.names = c(NA, 18L), class =
"data.frame")
>
> # split data frame according the the individual IDs
> wing.list <- split(WW_Wing_SI, WW_Wing_SI$Individual_ID)
>
> # apply cor.test() with extract to each element of the list
> test <- as.data.frame(t(sapply(wing.list, function(temp)
> cor.test(temp$Delta13C,
temp$FeatherPosition,
> method="pearson")[c("estimate",
> "p.value", "conf.int")])))
>
>
*******************************************************************************************
> Keith Larson, PhD Student
> Evolutionary Ecology, Lund University
> Sölvegatan 37
> 223 62 Lund Sweden
> Phone: +46 (0)46 2229014 Mobile: +46 (0)73 0465016 Fax: +46 (0)46
2224716
> Skype: sternacaspia FB: keith.w.lar...@gmail.com
If you unlist() the call to cor.test, you will end up with numeric data.
You will also end up with two variables for the confidence intervals.
test <- data.frame(t(sapply(wing.list, function(temp)
unlist(cor.test(temp$Delta13C, temp$FeatherPosition,
method="pearson")[c("estimate", "p.value", "conf.int")]))))
test
estimate.cor p.value conf.int1 conf.int2
WW_08A_02 -0.76706752 0.01585509 -0.9481677 -0.2098478
WW_08A_03 -0.02320767 0.95274294 -0.6768966 0.6509469
Jean
[[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.
