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...array ARR <- array(unlist(huge.list), dim = c(dim(huge.list[[1]]), length(huge.list))) # then split it and use abind function, but it didn't work Thanks in advance! Vladimir -- Vladimir Mikryukov PhD student Institute of Plant & Animal Ecology UD RAS, Lab. of Population and Community Ecotoxicology [8 Marta 202, 620144, Ekaterinburg, Russia] Tel. +7 343 210 38 58 (ext.290) Fax: +7 343 260 82 56, +7 343 260 65 00 [[alternative HTML version deleted]]

...do it with the long format of data one can run this code: library(reshape2) data.long <- melt(dat, measure.vars=c("Cond1", "Cond2"), variable.name ="Cond") -- Vladimir Mikryukov, PhD Institute of Plant & Animal Ecology UD RAS, Lab. of Population and Community Ecotoxicology [8 Marta 202, 620144, Ekaterinburg, Russia] [[alternative HTML version deleted]]

I am attempting to estimate LC50 (analogous to LD50, but uses exposure concentration rather than dose) by fitting a Weibull model; but I can't seem to get it to work. From what I can gather, I should be using survreg() from the survival package. The survreg() function relies on time-to-event data; my data result from 96 h exposures (i.e., dead or alive after a fixed period; 96 h). I've

...ng message: installation of package 'RODBC' had non-zero exit status in: install.packages(c("RODBC")) ************************ -- ======================================================= TOMASZ PUZYN, Ph.D. puzi at pcb.chem.univ.gda.pl Department of Environmental Chemistry and Ecotoxicology University of Gdansk, Faculty of Chemistry ul. Sobieskiego 18 80-952 Gdansk, Poland tel. +48 (58) 345 04 45 fax. +48 (58) 345 04 72 http://www.chem.univ.gda.pl/~zchsie

...ax(yy) b=min(yy) lines(c(xx[yy==a],xx[yy==b]),c(a,b)) Now I would like to know if it is possible to extrapolate the characteristic of the line (intercept and slope). Is it there and appropriate function for this? Thanks for your help! Ida D. -- Ida Dolciotti, M.Sc. Phd student, Dept. System Ecotoxicology Helmholtz Centre for Environmental Research - UFZ Permoserstr. 15 04318 Leipzig phone: +49 - 341/235-1498 fax: +49 - 341/235-1785 email: ida.dolciotti at ufz.de website: http://www.ufz.de/index.php?en=17738 ------------------------------ Message: 9 Date: Wed, 29 Jun 2011 16:49:10 +0700 From...

...array ARR <- array(unlist(huge.list), dim = c(dim(huge.list[[1]]), length(huge.list))) # then split it and use abind function, but it didn't work Thanks in advance! Vladimir -- Vladimir Mikryukov PhD student Institute of Plant & Animal Ecology UD RAS, Lab. of Population and Community Ecotoxicology [8 Marta 202, 620144, Ekaterinburg, Russia] Tel. +7 343 210 38 58 (ext.290) Fax: +7 343 260 82 56, +7 343 260 65 00 [[alternative HTML version deleted]] --Forwarded Message Attachment-- From: d.rizopoulos at erasmusmc.nl CC: r-help at r-project.org To: vmikryukov at gmail.com Date: T...