Thank you gentlemen for pointing me in the right direction. This code worked nicely:
countries <- list() for (i in 1:20) { countries[[i]] = as.matrix(subset(OECDFiscal2, Country == i)) } Take care, Taylor On Sun, Jun 24, 2012 at 3:01 PM, R. Michael Weylandt <michael.weyla...@gmail.com> wrote: > To elaborate on what Bert said: > > Lists are a variable length data structure which can hold most > anything (even other lists) in them and are a great way to organize > the sort of data you're working with. You can think of them as > "generic vectors." You can assign them names and access/subset them by > names or by element number. Perhaps most usefully, instead of passing > all the vectors to a function which may need them, you can simply pass > the one list object. This will make things much easier to maintain in > the long run/ > > Most everything complicated in R like data.frames or model objects are > internally implemented as lists (with various added features) and they > [lists] are exceptionally powerful. It will seem like more overhead > now than the lots-of-simple-vectors approach, but in the long run, it > will be most certainly worth it. > > Best, > Michael > > On Sun, Jun 24, 2012 at 4:30 PM, Bert Gunter <gunter.ber...@gene.com> wrote: >> Standard response: Use lists instead. >> >> Read An Intro to R to learn about lists. In fact,read an An Intro to R, >> full stop ( if you have not already done so). >> >> Cheers, >> Bert >> >> On Sun, Jun 24, 2012 at 2:15 PM, Taylor White >> <taylorgentrywh...@gmail.com>wrote: >> >>> Good day, >>> >>> For lack of a better solution (or perhaps I am ignorant to something >>> more elegant), I have been bootstrapping panel data by hand so to >>> speak and I would like to know if there is a way to define multiple >>> variables in a loop using the loop variable. I found a post (here: >>> https://stat.ethz.ch/pipermail/r-help/2002-October/026305.html ) that >>> discussed naming multiple variables but it didn't seem to allow me to >>> define the variables as something more useful. I tried the code >>> immediately below (plus some variations) and it just didn't work. >>> >>> for (i in 1:20) { >>> assign(paste("country.", i, sep = "") <- subset(OECDFiscal2, Country == i) >>> } >>> >>> >>> I included some sample code from what I've been working on below so >>> one can see how it would be very useful to figure out how to define a >>> series of variables from cross sectional units from a panel dataset. >>> >>> >>> Any help would be much appreciated. >>> >>> >>> Thanks, >>> >>> Taylor White >>> UCLA >>> >>> >>> >>> ######Bootstrapping panel data by hand. Create 4 variables from 3 >>> subsets of the original data. Resample each variable and recombine >>> into one matrix. >>> >>> >>> plmcoef <- array(0, c(1000, 4)) #creates an empty array to store >>> regression coefficients >>> plmfixef <- array(0, c(1000, 3)) #creates an empty array to store >>> fixed effects intercepts from regressions >>> >>> >>> for (i in 1:1000) { >>> country1 <- as.data.frame(subset(OECDFiscal2, Country == 1)) >>> country2 <- as.data.frame(subset(OECDFiscal2, Country == 2)) >>> country3 <- as.data.frame(subset(OECDFiscal2, Country == 3)) >>> >>> exp1 <- as.matrix(sample(country1$lagexpVSgdp, size = >>> (nrow(country1)), replace = T)) >>> exp2 <- as.matrix(sample(country2$lagexpVSgdp, size = >>> (nrow(country2)), replace = T)) >>> exp3 <- as.matrix(sample(country3$lagexpVSgdp, size = >>> (nrow(country3)), replace = T)) >>> >>> tax1 <- as.matrix(sample(country1$lagtaxVSgdp1, size = >>> (nrow(country1)), replace = T)) >>> tax2 <- as.matrix(sample(country2$lagtaxVSgdp1, size = >>> (nrow(country2)), replace = T)) >>> tax3 <- as.matrix(sample(country3$lagtaxVSgdp1, size = >>> (nrow(country3)), replace = T)) >>> >>> gdp1 <- as.matrix(sample(country1$yoygdpcapita, size = >>> (nrow(country1)), replace = T)) >>> gdp2 <- as.matrix(sample(country2$yoygdpcapita, size = >>> (nrow(country2)), replace = T)) >>> gdp3 <- as.matrix(sample(country3$yoygdpcapita, size = >>> (nrow(country3)), replace = T)) >>> >>> unemployment1 <- as.matrix(sample(country1$lagunemployment, size = >>> (nrow(country1)), replace = T)) >>> unemployment2 <- as.matrix(sample(country2$lagunemployment, size = >>> (nrow(country2)), replace = T)) >>> unemployment3 <- as.matrix(sample(country3$lagunemployment, size = >>> (nrow(country3)), replace = T)) >>> >>> country.year1 <- as.matrix(cbind(country1$Country, country1$Year2)) >>> country.year2 <- as.matrix(cbind(country2$Country, country2$Year2)) >>> country.year3 <- as.matrix(cbind(country3$Country, country3$Year2)) >>> >>> country1.2 <- as.data.frame(cbind(country.year1, exp1, tax1, gdp1, >>> unemployment1)) >>> country2.2 <- as.data.frame(cbind(country.year2, exp2, tax2, gdp2, >>> unemployment2)) >>> country3.2 <- as.data.frame(cbind(country.year3, exp3, tax3, gdp3, >>> unemployment3)) >>> >>> data <- as.data.frame(rbind(country1.2, country2.2, country3.2)) >>> >>> OECDsamplepanel <- pdata.frame(data, index = NULL, drop = F) >>> >>> plm <- plm(V5 ~ lag(V6, 1) + V3 + V4 + V5, data = OECDSamplepanel, >>> model = "within") >>> >>> coefficients <- t(as.matrix(plm$coefficients)) >>> fixef <- t(as.matrix(fixef(plm))) >>> >>> plmcoef[i, 1:4] = coefficients >>> plmfixef[i, 1:3] = fixef >>> >>> } >>> >>> ______________________________________________ >>> 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. >>> >> >> >> >> -- >> >> Bert Gunter >> Genentech Nonclinical Biostatistics >> >> Internal Contact Info: >> Phone: 467-7374 >> Website: >> http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm >> >> [[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. ______________________________________________ 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.