Ranney, Steven wrote:
Hmm. After checking my data, both the Spawner and Mtempcv columns are of equal lengths. While I could be wrong, recycling doesn't seem to be the issue.Notice that you have two "Spawner": One in the data, and one in newdata. These are probably not of the same length.
Well, it would, if mod2a is much larger than the Mtempcv from your data, and the coefficient is negative. How about predict(mod2, newdata=data.frame(Spawner=mod2a, Mtempcv=0.3)) ?As a relatively new user of R, I tried to adjust the newdata= issue by adding Mtempcv to the newdata= call (i.e., predict(mod2, list(Spawner=mod2a, Mtempcv=mod2a)). This eliminated the "longer object length is not a multiple..." warning message, but the plot produces only a flat line at 0 on the y axis.
-----Original Message----- From: Peter Dalgaard [mailto:[EMAIL PROTECTED] Sent: Thu 7/3/2008 3:07 PM To: Ranney, Steven Cc: r-help@r-project.org Subject: Re: [R] lines() warning messageRanney, Steven wrote:Hmm,,, The predict() call looks dodgy. The model depends on Spawner AND Mtempcv, but you're only giving the former in the newdata= part. So a good guess that one of them is recycled to the length of the other.I have data that looks like Year,Recruit,Spawner,Mtempcv 1958,4532,775,0.24125 1959,22996,2310,0.16319 1960,628,2990,0.46056 1961,879,1400,0.33028 1962,14747,1130,0.22618 1963,13205,790,0.20596 1964,31793,1195,0.19229 1965,10621,981,0.20363 1966,22271,870,0.3452 1967,8736,1104,0.27511 1968,8761,883,0.10884 1969,18885,1421,0.17799 1970,10098,1198,0.2106 1971,3394,760,0.22098 1972,1697,1354,0.39461 1973,25159,1308,0.19696 [truncated] with program #Ricker Curve mod2=nls(Recruit~(Spawner*exp((delta+echo*Spawner)+(foxtrot*Mtempcv))), data=box48, start=list(delta=4, echo=0, foxtrot=-7), trace=TRUE) plot(Recruit~Spawner, data=box48, pch=19) mod2a=seq(369, 3000) lines(mod2a, predict(mod2, list(Spawner=mod2a)), col="red", lty=2) R has no problem finding a solution to the nls() model (only 7 iterations are needed), but when I try to plot the line on the requested plot, I get the warning message "Warning message: In (delta + echo * Spawner) + (foxtrot * Mtempcv) : longer object length is not a multiple of shorter object length." R tries to plot the line, but it appears as just a mess of vertical lines that get more dense where (I would imagine) the actual line is to go. Any ideas what may be causing this issue?
-- O__ ---- Peter Dalgaard Øster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ 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.
