similar to: cross table

Hi, I'd like to find which values of x will give me a y. In other words, in the example of a gaussian curve, I want to find the values of x that will give me a density, let's say, of 0.02. curve(((1/(sqrt(2*pi)*10))*exp(-((x-50)^2)/(2*10^2))),xlim=c(0,100)) Thanks for any help, Antonio Olinto ------------------------------------------------- WebMail Bignet - O seu provedor do

Hi, I want to write in x axis label "fitted value of lambda" (lambda in greek letter). xlab=expression(lambda) gives the "lambda", I tryed things like xlab=paste ("fitted value of ", expression(lambda)) but I didn't get the greek letter. Thanks in advance for any hint. Antonio Olinto ------------------------------------------------- WebMail Bignet - O seu

Hi, I have doubts in using subset command. I have a list of, lets say, 15 species and I want to make a subset with only 2 of them. I??m the command data2 <- subset(data1, species=="sp1"|species=="sp2") Nevertheless, when I ask for the summary (summary(data2)) the others species names still apearing. Also I tried data2<-data1(data1$species %in%

Hello all, Here goes one of my first functions. I want to make a nonparametric multiple sample comparison with unequal sample sizes (see Zar?s Biostatistical Analysis, 3rd. Ed., pg. 201 Example 10.11, pg. 288 Example 11.10). In the real world, I want to compare samples of fish length captured with different fishing gears. After using the Kruskal-Wallis test I want to check the differences

Hello, I have a doubt in using the function step (step wise) to select glm models. Usually I apply the gamma distribution to analyze fishery data. To select the terms I use a routine where I first compare single term models to the null model (eg. U~1 vs. U~depth; U~1 vs. U~latitude; etc. ? where U= abundance) and, by means of the result given by a likelihook function applied for each comparison,

Hello, This is my first post to this list. Well, I tried to install Google Earth using WineTools but I got the "Unknown Graphics Card" error. I can open the program but Earth doesn't appear. I'm running Debian Sarge on a ASUS CUW(E)-FX motherboard (Intel 810 Chipset) and Gnome 2.10.2 inteface. Thanks for any help. Best regards, Antonio -- Ant?nio Olinto Biologist /

Hi, I have a data set with values (L) varying from 1 to 700, with repeated numbers, and I want to sample them according to the probabilities given by a logistic curve P=1/(1+e(-r*(L-Lc))) where r gives "S" the inclination and Lc the "rotation point". P ranges from 0 to 1. As I could see I cannot use this P as prob in sample function. I'd need the probabilities as given by

Hi, I?m trying to make a barplot with the following dataframe, with information on relative frequency per sediment type (ST) for some species: Species ST1 ST2 ST3 SP_A 10 60 30 ... At x-axis are (should be ...) the species names and at y-axis the frequency per sediment, in stacked bars. I tried to use barplot command but with no results. Could anyone help me on this? Thanks in

Thanks for your reply Nassar. What I really want is to overlay (like add=TRUE) the plots 1 and 2. With plots "at the same screen" I meant overlaid and not one beside the other, i.e., only one plot with all the points (1 to 10) in blue (or any other color), the points 5 to 9 in red and a regression line from points 5 to 9. Best regards, Antonio Olinto ----- Original Message -----

Dear R-list members Here goes a question on data frames: I want to create a new data frame excluding some records (rows) from an existing one. Considering the data frame "fish.dat" at the end of this message, I can make a boxplot(Ring~Radius) and identify the points at rows 11 and 25 as outliers. With the command fish.dat[c(11, 25),] I can identify which fishes are related to

Hello R-list members, I’m trying to make a min-avg-max plot (like a boxplot, without box and outliers, i.e., for each class of "x" a vertical line indicating the range (max-min) and an horizontal line or point indicating the mean) with data like: Year Avg Min Max 98 10 7 13 99 12 10 15 01 11 6 14 Which command should be used? Many thanks, Antonio Olinto

Hello, I want to know how do R calculates the number of intervals between tick-marks in the y axis in a plot. I'm making a three y-axes plot and this information would help me a lot. Thanks in advance. Antonio Olinto ---------------------------------------------------------------- Webmail - iBCMG Internet http://www.ibcmg.com.br

Dear list fellows, I want to study time series and use R to analyse time series of fishing data from several species (landings and cpue) investigating the correlation between them and with environmental factors (water temperature, wind, etc.). Searching at Amazon I found three books with examples in R: Time Series Analysis: With Applications in R by Jonathan D. Cryer and Jonathan D. Cryer

Hello all, I have a data frame with year, month, species, fishing gear and catch (Y, M, S, F, C) and I want the sum of C by Y for species "A" and fishing gear "trawl". I tried things like aggregate(C[S=="A" & F=="trawl"], list (Year = Y[S=="A" & F=="trawl"]), fun=sum), but it didn't worked. To overcome this problem I did

Dear R-list members, Some months ago I wrote a message on the usage of gnls (nlme library) and here I come again. Let me give an example: I have a 10 year length-at-age data set of 10 fishes (see growth.dat at the end of this message) and I want to fit a von Bertalanffy growth model, Li= Linf*(1-exp(-k*(ti-t0))) where Li = length at age i, Linf= asymptotic length, k= curvature parameter, ti=

Antonio, For linear regression we have the following identity total SS = regression SS + residual SS (*) where total SS is the sum of squares of observations around their mean, i.e. total SS = (n-1)*var(y) and residual SS is given by the deviance function. R-squared is defined as R^2 = regression SS/ total SS = 1 - residual SS/total SS. You can use this last formula

?summary.lm says, under the "Value" section, coefficients: a p x 4 matrix with columns for the estimated coefficient, its standard error, t-statistic and corresponding (two- sided) p-value. so try summary(fit.lm)$coefficients[,1:2] to get the coefficients and their SEs. For nls, it takes a bit more digging, as the documentation is a bit sparse. Something

Dear R-List members, I want to check if a set of measurements follows better a gamma or a lognormal distribution (see data below). Using shapiro.test I can test for normality (shapiro.test(log (Lt)). To test for gamma (and normal) distribution I would use ks.test but I need to specify its shape and scale. How should I calculate these values in R? I tried > Lt.fit <- glm(Lt ~ 1,

Hello, About looping, consider the example: for (i in 1:23194) { dat.stat[i,c(2:8)]<-quantile(dat.bat[BL==block[i],2],prob=c(0,0.025,0.25,0.5,0.75,0.975,1)) print(i) } I'd like to have the value of "i" printed for each loop (step). As I could see the values of "i" are shown on screen only after all the work is done. Thanks in advance for any suggestion. Best

Hi, Some time ago I asked about how to use comma as decimal separator in plots and Mr. Paul Murrell wrote: ------- You could try something with axis() and chartr(), like ... par(mfrow=c(2,1)) plot(1:10/11, rep(1, 10), main="Standard X-Axis") plot(1:10/11, rep(1, 10), main="Customised X-Axis", axes=F) axis(1, at=pretty(1:10/11),