similar to: matrix to coordinates

Dear R-collegues, I'm getting an error message (Error in round) when summarising a glm.nb model, and when using anova.negbin (in R 1.3.1 for windows): > m.nb <- glm.nb(tax ~ areal) > m.bn Call: glm.nb(formula = tax ~ areal, init.theta = 5.08829537115498, link = log) Coefficients: (Intercept) areal 3.03146 0.03182 Degrees of Freedom: 283 Total (i.e. Null); 282

I don't quite understand the difference between the two methods for performing a chi-squared test on contingency tables: summary(table()) and chisq.test() They may different results. E.g.: aa <- gl(2, 10) bb <- as.factor(c(1,2,2,2,1,2,1,2,2,2,1,2,2,2,1,1,1,2,1,1)) aa <- c(aa, aa) bb <- c(bb, bb) table(aa, bb) summary(table(aa, bb)) chisq.test(aa, bb) Could somebody give me

Hi, Thanks for showing me how to use RODBC and odbcConnect. Now works nicely. The question I've got now is: noms <- list.files(pattern=".DBF") # removing extension names: noms <- sapply(noms, function(x) as.character(strsplit(x,".DBF")) , USE.NAMES=F) for (i in 1:length(noms)) { s <- sqlFetch(bdades, noms[i]) # etc. } But it seems that sqlFetch()

Dear colleges, I'm trying to combine a barplot and a plot in a single figure as follows: data <- 1:6 t <- barplot(data, axes=F) par(new= T) plot(t, data, type="b") However, as you can see in the example, the dots of the second plot do not fall in the midpoint of the bars in the first. Any trick for setting the 2 plots at the same scale? I have unsuccessfully tried: plot(t,

Dear R collegues, I'm trying to understand what's AIC in R (ver. 1.3.1), and I'm getting a different answer if I look at the AIC(of the fitted model) or the aic in the summary( of the fitted model). Is this correct? Can somebody explain me the difference between the two values? or Is the AIC criterion not appropiated for Poisson models? R session: > t1 <- glm(tax ~ areal,

Dear R collegues, I'm trying to understand what's AIC in R (ver. 1.3.1), and I'm getting a different answer if I look at the AIC(of the fitted model) or the aic in the summary( of the fitted model). Is this correct? Can somebody explain me the difference between the two values? or Is the AIC criterion not appropiated for Poisson models? R session: > t1 <- glm(tax ~ areal,

R-users, Can an offset term be included in a Poisson model? I get an error message when trying that: >r3o <- glm(tax ~ areal + offset(o), family=poisson) Error in (if (is.empty.model(mt)) glm.fit.null else glm.fit)(x = X, y = Y, : inner loop 1; can't correct step size In addition: Warning message: Step size truncated due to divergence in: (if (is.empty.model(mt))

Is there a way of removing all rows with missing values from a data frame? I usually use subset(x, var1!="NA") and repeat for each variable. It would be nice to be able to do it in one fell swoop. Also, surprisingly, it doesn't always work. Sometimes I'm left with an empty set even though not all rows have missing values for the variable. Cheers, mikkel Mikkel Grum,

Hello everyone, When looking for information about clustering of spatial data in R I was directed towards DBSCAN. I've read some docs about it and theb new questions have arisen. DBSCAN requires some parameters, one of them is "distance". As my data are three dimensional, longitude, latitude and temperature, which "distance" should I use? which dimension is related to

Hola a todos Estoy intentando extraer un subconjunto de datos de una serie temporal, concretamente quiero extraer los meses de verano de varios años pero no encuentro la manera. Los datos tienen este formato: FECHA;H_SOLAR;DIR_M;DIR_S;VEL_M;VEL_S;VEL_X;U;V;TEMP_M;HR;BAT;PRECIP;RAD;UVA;UVB;FOG;GRID;

Hola a todos Estoy tratando de analizaruna serie temporal con datos diarios de temperaturas (40 años). He creado un objeto zoo (con ayuda de la lista, gracias) sobre el que encuentro la regresión lineal. He probado también a crear un objeto ts a partir del zoo. El problema que encuentro es que nose puede aplicar la función stl para hallar la componente estacional y la tendencia. Rdice que la

Dear all, I'm interested in analysing a reapeated measure desing where plant height (H) was measured 3 times (Time). The experimental design include 2 fixed factor (say A and B) in which A is nested in B, and a random factor (C, the plot), using the aov(). So my first idea would be something like: aov(H ~ B * A %in% B * Time + Error(id) ) where id is the factor coded for the repeated

Hi everyone As I couldn't succeed with manual installation of Rmpi I decided to start again from the beginning. I removed R and MPICH in my Ubuntu Hardy installation. Then, to avoid any dependencies problems I have installed MPICH and R from synaptic, not from sources. But now I can't install Rmpi. An error message appears when trying to install Rmpi, you can find in

Hi all, I have a large file (1.8 GB) with 900,000 lines that I would like to read. Each line is a string characters. Specifically I would like to randomly select 3000 lines. For smaller files, what I'm doing is: trs <- scan("myfile", what= character(), sep = "\n") trs<- trs[sample(length(trs), 3000)] And this works OK; however my computer seems not able to handle

Hi everyone I am trying to do some time series analysis with daily temperature data (40 years). I have created a zoo object and ts object but can't apply stl function. It says the series is not periodic or has less than two periods. I've searched through google and found a lot of messages about this problem but not a solution/example to look for trend and seasonal component of a

Dear colleagues, I'd like to reshape a datafame in a long format to a wide format, but I do not quite get what I want. Here is an example of the data I've have (dat): sp <- c("a", "a", "a", "a", "b", "b", "b", "c", "d", "d", "d", "d") tr <- c("A",

Hi everyone I am new to R and have a question about missing values. I am trying to do a cluster analysis of monthly temperatures and my data are 14 columns with spatial coordinates (lat,lon) and 12 monthly values: /lat - lon - temp1 - //temp2 - temp3 - .... - //temp12/ If I omit missing values (my missing values are 99.00) with /mydata <- na.omit(mydata)/ every row with a

Hi I'd like to write.table a dataframe, but with an specific order of columns. Is there a direct way to do it? or I have to generate a new dataframe as follows: t <- data.frame(c=1:10, b=11:20, a=letters[1:10]) t2 <- data.frame(a=t$a, b=t$b, c=t$c) write.table(t2, row.names=F) Thanks for any comment Juli -- http://www.ceam.es/pausas

Hi Is there a way to remove blank characters from the end of strings in a vector? Something like the =TRIM functions of the OpenOffice spreadsheet. E.g., a <- c("hola ", "Yes ", "hello ") # I'd like to get: c("hola", "Yes", "hello") Thanks Juli -- http://www.ceam.es/pausas

Hola a todos Estoy intentando hacer un análisis rápido de una serie temporal de datos diarios pero me encuentro con algunos problemas. Me gustaría en primera instancia hacer una regresión lineal pero no encuentro la forma. Tras leer los datos diarios creo un objeto de la clase zoo y sobre éste no puedo utilizar lm(). He leído algo sobre dynlm pero no encuentro la forma. Se agradece