similar to: How to catch data from the different dataframes and lm problem?

Dear all: I am a new R-user and I have 2 questions about it. 1) I need to find specific sub-dataframe, and then use specific column to calculate. For example, after splitting dataframe, I find specific the sub-dataframe, such as ?A.split [1]?. But, I don?t know how to find ?time? and ?concentration? columns of ?A.split [1]?. 2) The equation used to sub-dataframe is

Dear All: I need to have some data frame objects. First aa object: pH Formulation time Subject [1]1.2 F 0 1 [2]7.4 S 1 2 [3] MF 2 3 [4] 3 4 [5] n i Then, I need to produce 2*3(pH*formulation) different tables. This table includes column of (pH, Formulation, time S1 S2 S3 ?K..Si) and S1=

Dear R-users: I am a new R-user and I have a question about lm function. Here is my data. a<-c(1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,14,14) b<-c(1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2) c<-c(2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2) d<-c(2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1,2,2,1,1)

Hi! I'm just getting started with R (and with the analysis of large datasets in general). I have several beginner-level questions whose answers I have not been able to find, and was hoping one of you would be kind enough to throw me a cluebrick or two. I have a 6-dimensional numeric array (which I'll call myarray) that is "fully named". By this I mean that non-NULL dimnames

Hello R-help I have the following data for a standard curve concentration(nM),fluorescence 0,48.34 2,58.69 5,70.83 10,94.73 20,190.8 50,436.0 100, 957.9   (1)Is there function in R to plot a spline. (2)How can I interpolation,say 1000 point from 0nM-100nM and store this as a data frame of concentration,fluorescence (3)How can I modify the code below so that instead of retrieving a concentration

Hello-- I have a data for small population who took 1 drug at 3 different doses. I have the actual drug concentrations as well as predicted concentrations by my model. This is what I'm looking for: - Time vs Concentration by ID (individual plots), with each subject occupying 1 plot -- there is to be 9 plots per page (3x3) - Observed drug concentration is made up of points, and predicted drug

Hi, I've been modelling some data over the past few days, of my work, repeatedly challenging microbes to a certain concentration of cleaner, until the required concentration to inhibit or kill them increaces, at which point they are challenged to a slightly higher concentration each day. I'm doing ths for two different cleaners and I'm collecting the required concentration to

Dear R users, today I've got the following problem. Here you are a dataframe as example. There are some SAMPLES for which a CONCentration was recorded through TIME. The time during which the concentration was recorded is not always the same, 10 points for Sample A, 7 points for Sample B and 11 for sample C Also the initial concentration was not the same for the three samples. I would like

Hi, I am struggling to create a 2 by 2 multiple graphs in one page. I used par(mfrow=c(2,2)) to divide the screen into 4. In each screen I draw a pie chart (They are all same). For example, my data is like this Concentration value A1 69 A2 8 G1 51 G2 1

Greetings, I cannot find solution for this problem (I was searching on web, but without success): I want to plot dose-response models for one concentration and many responses (lets say 200) and I don?t want to do it manually. So I use loop for this: for (i in mydata[,2:201]){ #first column is concentration pdf(paste("plot_",i,".pdf",sep = ""))

Greetings, I have a question that I'd like to get input on. I have a classic toxicology study where I artificially fertilized and exposed embryos to a chemical and counted defects. In addition, I kept track of male-female pairs that I used to artificially fertilize and generate embryos with. I need to use logistic regression to model the response, but also check that the genetics of the

Hello, This is my first time addressing such a big audience so apologies in advance in case I fail to formulate this question. I am working with 13 species of trees, and the data I have are: 1 continuous (phenolic concentration in xylem and in phloem) and 2 categorical variables: lineage (3 subclades) and habitat (fire and non fire). I am trying to see how species can be splitted

What test do I use to determine if there is a correlation between a discrete variable and a continuous variable? For example - I have water quality ratings for streams (excellent, good, fair, poor) and a corresponding nitrogen concentration for each rating. I want to know if the the ratings correlate with the concentration of nitrogen in the stream. Help?

Dear All, I have a data sets as shown below A (Patient ID ), B and C are the Concentration of drug in blood on day 1 and day 4, D is the difference in conc. To do this in R I have written a code as follows, identified the number of patients who have more concentration on day 4 . Here I want to identify specifically the patient ID (is he patient 1 or 2 or 5 and 7), whose concentration is more. How

Hi, I just started a new course this semester on R, I never used it in my life and i'm stuck on these questions from 3 days, it would be really nice if someone could explain me the answers with the relative commands. thanks a lot in advance The following 7 questions are based on the CO2 dataset of R. 1) How many of the plants in CO2 are Mc2 for Plant? 2) How many are either Mc2 or Mn2?

Hello, I am using R, through rsruby, to create a graph and best fit line for a set of data points, regarding data collected in a Chemistry class. The problem is that although the graph functions perfectly properly, the best fit line will not work. I initially used code I pretty much copied from a website with a tutorial on this, which was: graphData.png("/code/Beer's-Law

Dear all, I'm trying reproduce an example of bioassays Yielding Concentration-Mortality Data particularly control - adjustment model from book Bioassay of Entomopathogenic Microbes and Nematodes chapter 7 with R. I used glm with family=binomial and link=probit, but I do not know how to implement parameter gamma (control mortality - mortality of the untreated control insect in this exaple)

A data frame has one factor, one date, and one numeric column. When I plot these using the default pch of the open circle (first attachment), xyplot(TDS ~ sampdate | she.s, data = sheep.cast, main = 'TDS in Sheep Creek', ylab = 'Concentration (mg/L)', xlab = 'Time') I see the higher concentration points toward the right on several panels. But, when I change to using a

Hello, Thank you very much for looking at this. I have a "seasonal" user for R. I teach my undergrads and graduates students statistics using R and often find myself trying to solve problems to process student collected data in an efficient way. In this case, I have a data.frame with multiple observations. These are gas concentrations in a chamber and are used to measure into rates,

Hello, I am struggling to figure out how to analyse a dataset I have inherited (please note this was conducted some time ago, so the data is as it is, and I know it isn't perfect!). A brief description of the experiment follows: Pots of grass were grown in 1l pots of standad potting medium for 1 month with a regular light and watering regime. At this point they were randomly given 1l of one