similar to: Stats Question

Displaying 20 results from an estimated 5000 matches similar to: "Stats Question"

2012 Oct 09
1
car::linearHypothesis Sum of Sqaures Error?
I am working with a RCB 2x2x3 ANCOVA, and I have noticed a difference in the calculation of sum of squares in a Type III calculation. Anova output is a follows: > Anova(aov(MSOIL~Forest+Burn*Thin*Moisture+ROCK,data=env3l),type=3) Anova Table (Type III tests) Response: MSOIL Sum Sq Df F value Pr(>F) (Intercept) 22.3682 1 53.2141 3.499e-07 *** Forest
2010 Jun 29
3
mixed-effects model with two fixed effects: interaction
Dear all, In a greenhouse experiment we tested performance of 4 different species (B,H,P,R) under 3 different water levels in 10 replications. As response variable e.g. the number of emerging sprouts were measured on three dates. A simple Anova considering every measurement date separately shows a higly significant effect of species and moisture (and partly the interaction of both). The
2005 Sep 26
2
nls and na/Nan/Inf error
I am trying to it a particular nonlinear model common in Soil Science to moisture release data from soil. I have written the function as shown below according to the logist example in Ch8 of Pinheiro & Bates. I am getting the following error (R version 2.1.1) *Error in qr(attr(rhs, "gradient")) : NA/NaN/Inf in foreign function call (arg 1)* Below is the function and data. /#
2000 Feb 10
2
random effects in analysis of variance
I have a data.frame paint (below-mentioned). In SPlus I used the command raov( MOISTURE ~ BATCH / PROBE ) (you could do raov( MOISTURE ~ BATCH + PROBE%in%BATCH) as well) so that the factors are taken as random. In R this function raov doesn't exist. How can I calculate the same? Maybe with lme, but how? str(paint) ---------- `data.frame': 60 obs. of 5 variables: $ BATCH : Factor
2011 Jun 22
1
Time-series analysis with treatment effects - statistical approach
Hello all R listers, I'm struggling to select an appropriate statistical method for my data set. I have collected soil moisture measurements every hour for 2 years. There are 75 sensors taking these automated measurements, spread evenly across 4 treatments and a control. I'm not interested in being able to predict soil future soil moisture trends, but rather in knowing whether the
2009 Aug 12
2
Superscripts in axis label
Hi All, I am trying to lable the y-axis on my scatterplot with the following: "Soil moisture content (m3m-3)" I am using the following coding for plotting the graph: plot(soilmoisture~gradientlevel, xlab="Levels of droughting gradient", ylab="Soil moisture content (m3m-3)", bty="l", font.main="2", pch=16, las=1, cex.lab="1.13") I have
2009 Jul 25
2
r2 question
Hi everyone, I have a question about calculating r-squared in R. I have tried searching the archives and couldn't find what I was looking for - but apologies if there is somewhere I can find this... I carried out a droughting experiment to test plant competition under limited water. I had: - 7 different levels of watering treatment (1 -7 - from most watered to least watered/) - 15
2014 May 10
2
[LLVMdev] Finding safe thread suspension points while JIT-ing (was: Add pass run listeners to the pass manager.)
So, I'm bringing a discussion that has thus far been on llvm-commits to llvmdev because I finally (and thanks for helping me understand this Andy) understand what is *really* going on, and I think lots of others need to be aware of this and involved to figure out the right path forward. You can find the full review thread and more context under the subject "[PATCH][PM] Add pass run
2011 Feb 15
1
Passing Arguments in a function
Hi All, I'm having some trouble assigning arguments inside a function to produce a plot from a model Can anyone help me? Below I've outlined the situation and examples of failing and working code. Regards Mike ## data ## decay.data <- ... behaviors lift reach.uu estimated.conversions.uu total.reach 1 1 432.0083 770 770 0.00 2
2013 Jan 06
1
nested, unbalanced anova
Hello, For an experiment, I selected plots of land within a forest either with honeysuckle or without honeysuckle. Thus, my main factor is fixed, with 2 levels: "honeysuckle present"(n=11) and "honeysuckle absent"(n=8). Within each plot of land, I have a "trenched" subplot and an "untrenched" subplot. Within each subplot of every plot, I measured soil
2010 Mar 13
1
Help needed: Split-split plot analysis
Hello, I am very new to R but would like to use the software to analyse the attached data. The experiment followed a split-split plot design There were two blocks and the whole plot is CO2 with two levels. The sub-plot is soil temperature with three levels and the sub-sub plot is soil moisture content with three levels (low, intermediate and high-similar for soil temperature). I had 7 plants per
2014 May 10
3
[LLVMdev] Finding safe thread suspension points while JIT-ing (was: Add pass run listeners to the pass manager.)
On May 9, 2014, at 7:36 PM, Andrew Trick <atrick at apple.com> wrote: > > On May 9, 2014, at 6:33 PM, Chandler Carruth <chandlerc at google.com> wrote: > >> So, I'm bringing a discussion that has thus far been on llvm-commits to llvmdev because I finally (and thanks for helping me understand this Andy) understand what is *really* going on, and I think lots of
2001 Dec 14
1
nls fit to exponential decay with unknown time origin
I'm trying to use nls() to fit an exponential decay with an unknown offset in the time (independent variable). (Perhaps this is inherently very difficult?). > decay.pl <- nls (amp ~ expn(b0,b1,tau,t0,t), data = decay, + start = c(b0=1, b1=7.5, tau=3.5, t0=0.1), trace=T) Error in nlsModel(formula, mf, start) : singular gradient matrix at initial parameter estimates
2004 Mar 30
1
classification with nnet: handling unequal class sizes
I hope this question is adequate for this list I use the nnet code from V&R p. 348: The very nice and general function CVnn2() to choose the number of hidden units and the amount of weight decay by an inner cross-validation- with a slight modification to use it for classification (see below). My data has 2 classes with unequal size: 45 observations for classI and 116 obs. for classII With
2014 May 13
3
[LLVMdev] Finding safe thread suspension points while JIT-ing (was: Add pass run listeners to the pass manager.)
On May 12, 2014, at 3:52 PM, Philip Reames <listmail at philipreames.com> wrote: > I don't have a strong opinion on this topic at the moment, but given that it is potentially GC related, I figured I'd speak up. > > I see two unspoken assumptions in the thread so far: > - The runtime needs a means to bring all threads to a stop to perform some action. In particular,
2011 Apr 06
3
Getting number of students with zeroes in long format
Hi, I have longitudinal school suspension data on students. I would like to figure out how many students (id_r) have no suspensions (sus), i.e. have a code of '0'. My data is in long format and the first 20 records look like the following: > suslm[1:20,c(1,7)] id_r sus 11 0 15 10 16 0 18 0 19 0 19 0 20 0 21 0 21 0 22 0 24 0 24
2004 Apr 26
2
Looking for help in calculating percentiles
Hi All: I am working with a dataset on Arsenic toxicity, and I am trying to calculate the 20th, 40th, 60th, 80th, and highest percentiles for a variable, dietary Moisture (variable name dMoist). The inbuilt function quantile(dMoist) would print 0, 25th, 50th, 75th, and 100th percentile. Does there exist a function that can calculate xth percentile (where x = 10th, 20th, ... etc) values?
2010 Jul 01
3
Calculate area under a curve
Hi, I want to know the area under a curve, which is not given as a function, but as values in a time series. It is not a smooth curve, but switches often between positive values and zero (the values describe the moisture in the soil over a year, one entry is one day). I already tried area.between.curves, but got only 0 as result. I guess, it doesn't work because of these multiple changes
2012 Apr 14
2
master thesis
Hi, For my master thesis I have 24 micro-plots on which I did measurements during 3 months. The measurements were: - Rainfall and runoff events throughout 3monts (runoff being dependant on the rainfall, a coefficient (%) has been made per rainfall event and per 3 months) - Soil texture (3 different textures were differentiated) - Slope (3 classes of slopes) - Stoniness (one time measurement)
2004 Jun 14
2
CVnn2 + nnet question
Hi, I am trying to determine the number of units in the hidden layer and the decay rate using the CVnn2 script found in MASS directory (reference: pg 348,MASS-4). The model that I am using is in the form of Y ~ X1 + X2 + X3... + X11 and the underlying data is time-series in nature. I found the MASS and nnet package extremely useful (many thanks to the contributors). However I am getting