search for: growth

...39;ve not been able to find any solution that I could get working on my data. I was wondering if someone could look at my code and tell me what I'm doing wrong. I was hoping somebody's found a way to do this (I'm sure they have) and can tell me how to fix my code. # Input example data growth <- c(6.6,7.2,6.9,8.3,7.9,9.2,8.3,8.7,8.1,8.5,9.1,9.0) diet <- as.factor(rep(c("A","B","C"),2,each=2)) coat <- as.factor(rep(c("light","dark"),each=6)) growth.means <- aggregate(growth,list(coat,diet),mean) library(plotrix) growth.errs...

I'm a programmer in a biology lab who is starting to use R to automate some of our statistical analysis of growth rate determination. But I'm running into some problems as I re-code. 1) Hypotheses concerning Slope similarity/difference: I'm using R's anova(lm()) methods to analyse a model which looks like this: growth.metric ~ time * test.tube I understand that testing the the...

I apologize if this comes across as confusing. I will try to explain my situation as best I can. I have R bootstrapping my growth data for fish. It's resampling my database of age and length data and then produces several new datasets for me. In this case, it's resampling my data to create three new datasets of age and length data. Here is my code with my original data called growth: replicate(3, growth[sampl...

Hi, This is not a sophisticated statistics question as the subject suggests. But I am logging data - number of user sessions in a web application - before and after new users are migrated. I use R to graph but I am looking for a way to quantify the growth in the number of user sessions. As more users are now using the web application there is a growth. What is the way to measure this growth if I have time and number of sessions in a two data sets - before the growth and after the growth ? Thanks, Mohan This e-Mail may contain proprietary and...

I would like to install the package "growth" as it contains the function "corgram" and some other presumably useful stuff for time series analysis. I can see it is in R standard library list: http://hosho.ees.hokudai.ac.jp/~kubo/Rdoc/doc/html/packages.html<http://hosho.ees.hokudai.ac.jp/%7Ekubo/Rdoc/doc/html/packages.html&g...

What is the R way of computing cumulative growth rates given a series of discrete values indexed . For instance, given a matrix of 20 observations for each of 5 series (zz), what is the most straight forward technique in R for computing cumulative growth (zzcum) ? It seems for the solution I'm after might be imbedding the following cum g...

Dear all, I am running matrix population models using package "popbio". In a deterministic model {i.e., transition matrix is defined as A <- matrix(c(0.70, 0.70,0.35,0.50), nrow=2,byrow=TRUE}, population growth rate can be estimated from the dominant eigenvalue {command "eigen.analysis"}. However, I cannot figure out the way to compute the asymptotic stochastic population growth rate using ?popbio?. I would like to perform a stochastic model in which my demographic rates are sampled from beta d...

Hi, The data (attached) I am looking at consists of measurements of growth rate at different ages, for individuals in two treatments (control and infected). What I want to know is whether and when (what age) the growth rate of infected individuals is higher than the growth rate for control individuals. The simplest way to approach this question is to just do a t-test at...

We are constructing growth charts (age/weight and age/length) for children with diagnosis that impacts weight/length. But we we don't know how to use R for producing growth charts. We are collection data of Age, Weight and Length. The data are used to produce diagnosis-specific Growth charts (like the CDC Growth Char...

...libraries works but on loading > library(repeated) Loading required package: rmutil Error in dyn.load(file) : unable to load shared library "/usr/local/lib/R/library/repeated/libs/repeated.so": /usr/local/lib/R/library/repeated/libs/repeated.so: undefined symbol: do_lio > library(growth) Error in dyn.load(file) : unable to load shared library "/usr/local/lib/R/library/growth/libs/growth.so": /usr/local/lib/R/library/growth/libs/growth.so: undefined symbol: trans_ I would be greatful for tips from someone who has managed to get these working on a RedHat Linux (or other...

Hi everyone, I have a quick and probably easy question about lme for this list. Say, for instance you want to model growth in pituitary distance as a function of age in the Orthodont dataset. fm1 = lme(distance ~ I(age-8), random = ~ 1 + I(age-8) | Subject, data = Orthodont) You notice that there is substantial variability in the intercepts (initial distance) for people at 8 years, and that this variability in initi...

Dear all, I have some growth curve data from an experiment that I try to fit using lm and lmer. The curves describe the growth of classification accuracy with the amount of training data t, so basically y ~ 0 + t (there is no intercept because y=0 at t0) Since the growth is somewhat nonlinear *and* in order to estimate the t...

I'm trying to understand how to plot individual growth curve trajectories, with the overall mean trajectory superimposed (preferably in a slightly thicker line, maybe in black) over the individual trajectories. Using the sleepstudy data in lme4, here is the code I have so far: library(lme4) library(lattice) xyplot(Reaction ~ Days, data = sleepstudy,...

I am analyzing a dataset on the effects of six pesticides on population growth rate of a predatory mite. The response variable is the population growth rate of the mite (ranges from negative to positive) and the exploratory variable is a categorical variable (treatment). The experiment was blocked in time (3 blocks / replicates per block) and it is unbalanced - at least 1 rep...

Dear all, I am a total beginner in R, so sorry if this is the wrong place. I am using R 2.10.1 on a Mac (Mac OS 10.6.2). I have this small dataset : growth sugar 75 C 72 C 73 C 61 F 67 F 64 F 62 S 63 S I have no problem reading the table, or getting the summary, but if I try boxplot(growth~sugar, ylab="growth", xlab="sugar", data=Dataset), I have the following error : ERROR: unused argument(s) (sugar). Any suggestions ?...

Hi R user, Would you mind to help me to find the range with stochastic events? For example, daT<-structure(list(sn = 1:14, growthrate = c(0.5, 0.6, 0.7, 0.99, 0.1, 0.3, 0.4, 0.5, 0.5, 0.2, 0.1, 0.4, 0.3, 0.43)), .Names = c("sn", "growthrate"), class = "data.frame", row.names = c(NA, -14L)) I want to find the ranges of growth rate of the above data using Mote corle simulation (9999 times) under t...

Hello, Having measured two populations' characteristics at one particular time[with great precision] with R, I would like to extend this to measuring the same populations starting at t1, and then again at t2, and try to develop a growth model (something like dpop1/dt=r*pop^(...),dpop2/dt=r*pop^(...)). I think the idea is to create a model that will predict the growth of a population(N(mu, sigma)) within a margin of error. This kind of modeling isn't well known or publicized in terms of R, am I right? regards, s

Dear R-list members, Cynthia M. Jones wrote a paper (Fitting growth curves to retrospective size-at-age data, Fisheries Research 46(2000):123-129; abstract at http://www.elsevier.nl/gej-ng/10/19/44/70/24/37/abstract.html)where the SAS procedure MIXED, Macro NLINMIX (Littell et. al., 1996)was used to estimate the von Bertalanffy growth function parameters assuming t...

...and sd of 16 cogat<-rnorm(1000,100,16) #Create a dataframe of MAP, ITBS, and CogAT data <- data.frame(map, itbs, cogat) #Draw from the multivariate distribution defined by MAP, ITBS, and CogAT means and the covariance matrix sim <- mvrnorm(1000, mu=mean(data), sigma, empirical=FALSE) #Set growth at 0 growth=0 #Combine elements into a single dataset simtest=data.frame (subject=subject, treat=treat,lunch, age=round(age,0),round(sim,0),growth) #Set mean growth by treatment condition with treatd subjects having a mean growth of 1.5 and non-treated having a mean growth of 0.1 simtest<-transf...

Dear All, I am given some noisy data which (by naked eye) appears to be oscillating first but finally growing. Is there any statistical set (I mean something different from e.g. a linear fit, which would not be convincing at all in my case) to detect growth (possibly without relying on any data fitting)? Many thanks Lorenzo