similar to: Question regarding extrapolation

Displaying 20 results from an estimated 2000 matches similar to: "Question regarding extrapolation"

2024 Jan 14
0
Plotting extrapolation with R like AUTOBOX does
Dear R-experts, I write to you to know if somebody is aware of a R package (or function) able to plot graphs for extrapolation. I need to be clear on what extrapolation really is to me. It is when we use the model for X variables outside the range of X variables that were used to construct the model and estimates.? What I am really looking for is that beyond confidence intervals for predictions
2012 May 21
0
linear extrapolation using data from imported text file
Dear?R experts, ? I?am trying to do linear extrapolation on a dataset?like the attached document. I looked at the approx and approxfun function that seem to do this function, but not fully understand them. I was wondering if someone could help with writing commands to do the following based on the attached file's example: ? ID#1 and ID?#2 both have response parameters ("MEASUREMENT"
2014 Jul 08
0
Extrapolation of rarefaction curve
Hi all, I used R (vegan package) to make rarefaction curves and I calculated the Chao index for each curve. However, the plateau is far from reached. What I want to do now is the following: Based on the Chao index, I want to extrapolate the curve so I get an x-value which gives me an estimation of the total number of clones I'd have to pick up and sequence in order to have a full coverage of
2023 Oct 26
2
Plot for 10 years extrapolation
Dear R-Experts, Here below my R code working but I don't know how to complete/finish my R code to get the final plot with the extrapolation for the10 more years. Indeed, I try to extrapolate my data with a linear fit over the next 10 years. So I create a date sequence for the next 10 years and store as a dataframe to make the prediction possible. Now, I am trying to get the plot with the
2011 Jan 29
1
data extrapolation function
Readers, Data was imported using the read csv command: dataimport<-read.csv("/path/to/dataimport.csv") 10,2000 12,2001 13,2002 15,2003 17,2004 Using the help contents for 'predict.lm' (i.e. ?predict.lm) a new data frame was created dataimportextra<-data.frame(x=seq(1990,2010,1)) predict(lm(dataimport),dataimportextra[,2],se.fit=TRUE)
2010 May 26
2
Survival analysis extrapolation
Dear all, I'm trying to fit a curve to some 1 year failure-time data, so that I can extrapolate and predict failure rates up to 3 years. The data is in the general form: Treatment Time Status Treatment A 28 0 Treatment B 28 0 Treatment B 28 0 Treatment A 28
2009 Apr 14
4
Forcing the extrapolation of loess through the origin
Hi all, I'm fitting a line to my dataset. Later I want to predict missing values that exceed the [min,max] interval of my empirical data, therefore I choose surface="direct" for extrapolation. l1<-loess(y1~x1,span=0.1,data.frame(x=x1,y=y1),control=loess.control(surface="direct")) In my application it is highly important that the fitted line intercepts at the point of
1999 Nov 24
1
Need help..
Dear All, I am trying to generate some Pareto random variates using the inverse method. This is really straightfoward and my R function looks as below : pareto <- function(c, a, cnt=1000) { u <- runif(cnt) x <- (c / ((u ^ (1 / a)))) mean.theo <- ((c * a) / (a - 1)) mean.gen <- mean(x) cat('Pareto mean : theoritical', mean.theo, 'generated', mean.gen,
2006 Oct 12
3
Extrapolated regression lines
Dear list members, When I create a simple scatterplot with a regression line (se below) the line is automatically extrapolated outside the range of data points. Why is this and how can I prevent R from extrapolating the regression line? Thank you in advance, Johan model<-lm(Herb~Para) plot(Para,Herb) abline(model)
2011 Apr 20
1
Extrapolating data points for individuals who lack them
Hi, We have an experiment where individuals responses were measured over 5 days. Some responses were not obtained because we only allowed individuals to respond within a limited time-frame. These individuals are given the maximum response time as they did not respond, yet we feel they may have done if given time (and by looking at the rest of their responses over time, the non-response days stand
2009 Feb 18
1
ggplot2 Y axis labels
Hi all: Using the example below, is there a way to add Y axis titles to each graphic instead of sharing the same title? library(ggplot2) RT = matrix(c(814, 500, 424, 394, 967, 574, 472, 446),4,2) colnames(RT) = c('repetition','alternation') rownames(RT) = c('7-yrs','11-yrs','15-yrs','21-yrs') rt <- melt(RT) names(rt) <- c("age",
2011 Feb 07
0
Combining the results from two simple linear regression models
Hi all. This is more of a stats question, I suppose. Let's say I have two separate simple regressions of weight on year from two different datasets. I want to combine the regressions so that I can come up with a single equation for the total weight regressed on year. In reality, there is missing data, so I can't just sum the data across datasets and come up with a regression on the
2005 Dec 20
2
need 95% confidence interval bands on cubic extrapolation
Dear R experts: I need to get this plot, but also with 95% confidence interval bands: hour <- c(1, 2, 3, 4, 5, 6) millivolts <- c(3.5, 5, 7.5, 13, 40, 58) plot(hour, millivolts, xlim=c(1,10), ylim=c(0,1000)) pm <- lm(millivolts ~ poly(hour, 3)) curve(predict(pm, data.frame(hour=x)), add=TRUE) How can the 95% confidence interval band curves be plotted too? Sincerely,
2019 May 10
0
[R] approx with NAs --> new argument 'na.rm=TRUE' ?!
I have now committed a version "fulfilling" your wish, partly at least, to R-devel . In the new approx(*, na.rm=FALSE) cases, the result of how NA's are treated does depend on the 4 different extrapolation rules {1, 2, 1:2, 2:1} The main reason was that I kept the low level code in C to do +- what it did before which automatically was using 'rule' to determine these
2009 Feb 19
4
type III effect from glm()
Hi all, This could be naivety/stupidity on my part rather than a problem with model output, but here goes.... I have fitted a fairly simple model m1<-glm(count~siteall+yrs+yrs:district,family=quasipoisson,weights=weight,data=m[x[[i]],]) I want to know if yrs (a continuous variable) has a significant unique effect in the model, so I fit a simplified model with the main effect ommitted...
2005 Apr 09
1
OT: ManxPower 2005 European Tour
I've helped a lot of people on the mailing lists and on IRC #asterisk. and wanted to let people know that I will be in Europe between May 19 and June 21. Stockholm (VON 2005), Brussels (holiday/vacation), Amsterdam (holiday/vacation), and Madrid (Astricon). There are several weeks during my trip that I have no current plans for and may add other cities to my itinerary. I'm looking
2005 May 05
2
Numerical Derivative / Numerical Differentiation of unknown funct ion
Hi, I have been trying to do numerical differentiation using R. I found some old S code using Richardson Extrapolation which I managed to get to work. I am posting it here in case anyone needs it. ######################################################################## richardson.grad <- function(func, x, d=0.01, eps=1e-4, r=6, show=F){ # This function calculates a numerical approximation
2012 Sep 25
1
Extrapolating Cox predicted risk
Dear all I generated predicted risk of death for each subject in the study by means of Cox proportional hazards model at 8 year of follow-up, a time point at which follow-up was more than 90% complete. It is possible to extrapolate to 10-year the predicted risk of each subjet by assuming an exponential distribution? Any help would be greatly appreciated. Thanks for your consideration.
2011 Jan 27
2
Extrapolating values from a glm fit
Dear R-help, I have fitted a glm logistic function to dichotomous forced choices responses varying according to time interval between two stimulus. x values are time separation in miliseconds, and the y values are proportion responses for one of the stimulus. Now I am trying to extrapolate x values for the y value (proportion) at .25, .5, and .75. I have tried several predict parameters, and they
2012 Jun 15
1
Divide all rows of a data frame by the first row.
Folks, I call the function calcAmorts like so: calcAmorts(prevAm, amort, myDates) Note that I use the package lubridate. The last line where do.call is called to first divide all the rows by the first row and then rbind gives the following error: Error in do.call("rbind", apply(amortsByYears, 1, "/", amortsByYears[, : second argument must be a list By contrast if