similar to: optimize calculations

Displaying 20 results from an estimated 2000 matches similar to: "optimize calculations"

2007 Feb 22
0
confidence intervals
Hi, I'm having trouble with the confidence interval of the nls function. I did my home work, and searched acros the support list until I came up with following solution of Peter Dalgaard: example(predict.nls) se.fit <- sqrt(apply(attr(predict(fm,list(Time = tt)),"gradient"),1, function(x) sum(vcov(fm)*outer(x,x)))) matplot(tt,
2013 Jan 24
4
sorting/grouping/classification problem?
Hi, I'm a database admin for a database which manage chromatographic results of products during stability studies. I use R for the reporting of the results in MS Word through R2wd. But now I think I need your help: suppose we have the following data frame: ID rrt Mnd Result 1 0.45 0 0.10 1 0.48 0 0.30 1 1.24 0 0.50 2 0.45 3 0.20 2 0.48 3 0.60 2 1.22 3 0.40 3
2010 May 11
0
[Fwd: Re: Plotting log-axis with the exponential base to a plot with the default logarithm base 10]
Is it the tick labels that you want to change? -----Original Message----- From: "Elisabeth Bjerke Rastad" <ebr024 at post.uit.no> To: "r-help at r-project.org" <r-help at r-project.org> Sent: 5/10/10 11:20 AM Subject: [R] [Fwd: Re: Plotting log-axis with the exponential base to a plot with the default logarithm base 10] Hello! Thank you for answering! What I am
2010 May 10
2
[Fwd: Re: Plotting log-axis with the exponential base to a plot with the default logarithm base 10]
Hello! Thank you for answering! What I am trying to do is to plot my raw values (biomass of different species) on a logaritmic y-axis with the base of e. When I type "log="y"", the axis transforms into a logaritmic axis with the base of 10. Best regards, Elisabeth > Dear Elisabeth, > > I'm not sure if I have understood your question -- are you trying > to
2010 May 09
3
Plotting log-axis with the exponential base to a plot with the default logarithm base 10
Hello! I have a problem which I have tried to solve for several days now.. I have plottet a lineplot.CI in the library "sciplot", and I am trying to plot it with a logaritmic y-axis (with exponential base). The problem is that; when I type "log "y"", the axis transforms into the logaritmic of base 10. I wonder if someeone could tell me how to specify that I would
2009 Feb 03
3
Problem about SARMA model forcasting
Hello, Guys: I'm from China, my English is poor and I'm new to R. The first message I sent to R help meets some problems, so I send again. Hope that I can get useful suggestions from you warm-hearted guys. Thanks. I builded a multiplicative seasonal ARMA model to a series named "cDownRange". And the order is (1,1)*(0,1)45 The regular AR=1; regular MA=1; seasonal AR=0; seasonal
2013 Feb 12
0
error message from predict.coxph
In one particular situation predict.coxph gives an error message. Namely: stratified data, predict='expected', new data, se=TRUE. I think I found the error but I'll leave that to you to decide. Thanks, Chris ######## CODE library(survival) set.seed(20121221) nn <- 10 # sample size in each group lambda0 <- 0.1 # event rate in group 0 lambda1 <- 0.2 # event rate in group 1
2010 May 09
1
Plotting log-axis with the exponential base to a plot wi
Hello Ted! Thank you a lot for your reply!!! I will try to explain again; what I want is a logarithmic scaled y-axis with the base of e (not 10). And the values I would like to use in the plot are the raw values (not transformed in any way). Do you still think that the base of log does not matter in this case (wheather it is e or 10 as a base)? Elisabeth > On 09-May-10 18:10:27, Elisabeth
2010 Jan 28
2
Data.frame manipulation
Hi All, I'm conducting a meta-analysis and have taken a data.frame with multiple rows per study (for each effect size) and performed a weighted average of effect size for each study. This results in a reduced # of rows. I am particularly interested in simply reducing the additional variables in the data.frame to the first row of the corresponding id variable. For example:
2010 Sep 26
1
formatting data for predict()
I'm trying to get predicted probabilities out of a regression model, but am having trouble with the "newdata" option in the predict() function. Suppose I have a model with two independent variables, like this: y=rbinom(100, 1, .3) x1=rbinom(100, 1, .5) x2=rnorm(100, 3, 2) mod=glm(y ~ x1 + x2, family=binomial) I can then get the predicted probabilities for the two values of
2011 Aug 23
1
P values for vglm(zibinomial) function in VGAM
Hi , I know this question has been asked twice in the past but to my knowldege, it still hasn't been solved. I am doing a zero inflated binomial model using the VGAM package, I need to obtain p values for my Tvalues in the vglm output. code is as follows > mod2=vglm(dmat~Season+Diel+Tidal.phase+Tidal.cycle,zibinomial, data=mp1) > summary(mod2) Call: vglm(formula = dmat ~ Season +
2004 Nov 17
1
R: log-normal distribution and shapiro test
Hi, from what you're writing: "The logaritmic transformation "shapiro.test(log10(y))" says: W=0.9773, p-value= 2.512e-05." it seems the log-values are not distributed normally and so original data are not distributed like a log-normal: the p-value is extremally small! Other tests for normality are available in package: nortest compare the log-transformation of your ecdf
2010 Jul 09
1
output without quotes
Hi All, I am interested in printing column names without quotes and am struggling to do it properly. The tough part is that I am interested in using these column names for a function within a function (e.g., lm() within a wrapper function). Therefore, cat() doesnt seem appropriate and print() is not what I need. Ideas? # sample data mod1 <- rnorm(20, 10, 2) mod2 <- rnorm(20, 5, 1) dat
2012 Jun 06
3
Sobel's test for mediation and lme4/nlme
Hello, Any advice or pointers for implementing Sobel's test for mediation in 2-level model setting? For fitting the hierarchical models, I am using "lme4" but could also revert to "nlme" since it is a relatively simple varying intercept model and they yield identical estimates. I apologize for this is an R question with an embedded statistical question. I noticed that a
2004 May 28
0
Merging nlme output
Dear list: I am trying to merge two files together from output I get based on the coef() command. Here is what I am running into. I have two simple linear mixed models > mod1.lme<-lme(math~year, data=sample, random=~year|childid/schoolid) > mod2.lme<-lme(math~year, data=sample, random=~year|childid) I then call the coefficients and store them in the following objects using >
2007 Nov 21
1
fitting a line to a logaritmic plot
Hi, I have processed measurements of a rough surface to a heigh-height correlation plot. What the meaning of this exactly is, is not important. Only that it is a plot that had two (almost ) linear parts when plotted on a logaritmic scale. In this plot, I want to draw the best fitting lines for these linear parts but I just can't get it done. It is easy when the scales are linear but as you
2013 Nov 25
0
R: lmer specification for random effects: contradictory reults
Dear Thierry, thank you for the quick reply. I have only one question about the approach you proposed. As you suggested, imagine that the model we end up after the model selection procedure is: mod2.1 <- lmer(dT_purs ~ T + Z + (1 +T+Z| subject), data =x, REML= FALSE) According to the common procedures specified in many manuals and recent papers, if I want to compute the p_values relative to
2023 Nov 30
1
back tick names with predict function
?s 17:38 de 30/11/2023, Robert Baer escreveu: > I am having trouble using back ticks with the R extractor function > 'predict' and an lm() model.? I'm trying too construct some nice vectors > that can be used for plotting the two types of regression intervals.? I > think it works with normal column heading names but it fails when I have > "special"
2012 Oct 15
0
Error message with the effects package - 'Subscript out of bounds'
I am using the effects package to construct some probability graphs showing the predicted probabilities from a logistic regression model. However, I get an odd error message and don't know what the issue is. When I attempt to generate the plots, I get the following error: dat$won_ping = as.factor(dat$won_ping) mod2 = glm(won_ping ~ our_bid + age_of_oldest_driver2 + credit_type2 +
2008 Oct 16
1
lmer for two models followed by anova to compare the two models
Dear Colleagues, I run this model: mod1 <- lmer(x~category+subcomp+category*subcomp+(1|id),data=impchiefsrm) obtain this summary result: Linear mixed-effects model fit by REML Formula: x ~ category + subcomp + category * subcomp + (1 | id) Data: impchiefsrm AIC BIC logLik MLdeviance REMLdeviance 4102 4670 -1954 3665 3908 Random effects: Groups Name Variance