search for: systematic

Displaying 20 results from an estimated 679 matches for "systematic".

2009 Jul 29
1
Systematic resampling (in sequential Monte Carlo)
..."how can I do this efficiently?" rather than "how can I do this?" (I know how to do it inefficiently). So, if you want to take the challenge, keep reading, otherwise just skip to the next post - I won't be offended by that ;-) I am coding a particle filter and I want to use systematic resampling to "regenerate" particles. Basically, what this means is the following. 1. Start with a vector of "labels", x, say, of length N and a vector of probabilities, w, say - w[i] is the probability attached to x[i]. 2. Draw N equally spaced random number in (0,1) as u...
2011 Jun 22
1
Subsetting data systematically
...owever, I don't want to use sample() because it does it randomly. I would like to take non-random subsamples, for example, every 2nd number, or every 3rd number. Is there a procedure that does this? Thanks, Nate -- View this message in context: http://r.789695.n4.nabble.com/Subsetting-data-systematically-tp3618516p3618516.html Sent from the R help mailing list archive at Nabble.com.
2013 Jan 19
1
dummy encoding in metafor
...ch I have to dummy encode. I have found the following piece of code in the manual for the metafor library: ### manual dummy coding of the allocation factor alloc.random <- ifelse(dat$alloc == "random", 1, 0) alloc.alternate <- ifelse(dat$alloc == "alternate", 1, 0) alloc.systematic <- ifelse(dat$alloc == "systematic", 1, 0) ### test the allocation factor (in the presence of the other moderators) ### note: "alternate" is the reference level of the allocation factor ### note: the intercept is the first coefficient, so btt=c(2,3) rma(yi, vi, mods=cbind(al...
2003 Feb 24
3
Test suites
I have a collection of functions, class definitions and methods which I would like to test systematically for their correctness after changes to their code, and also after major R revisions. I believe that the correct term for these systematic tests (as opposed to more informal tests) is a 'test suite'. Does anyone [apart from Pat Burns :-) ] have code, or templates, or specific suggestio...
2008 Aug 27
4
Fw: How to learn R language?
...<saggak1908@yahoo.co.in> wrote: From: saggak <saggak1908@yahoo.co.in> Subject: How to learn R language? To: r-help@r-project.org Date: Wednesday, 27 August, 2008, 3:37 PM Hi! I am a post graduate in Statistics. I want to learn R language, but am very confused as to how to begin systematically. I need to learn R language from Statistics point of view e.g. I need to fit distributions to data or run regression analysis etc. No doubt there are so many articles available on internet. But can someone guide me as to how do I begin and go on improving myself SYSTEMATICALLY? Hence, please g...
2008 Aug 27
2
How to learn R language?
Hi! I am a post graduate in Statistics. I want to learn R language, but am very confused as to how to begin systematically. I need to learn R language from Statistics point of view e.g. I need to fit distributions to data or run regression analysis etc. No doubt there are so many articles available on internet. But can someone guide me as to how do I begin and go on improving myself SYSTEMATICALLY? Hence, please g...
2005 May 19
0
Random/systematic selection of rows in a matrix
Hi R people: I am new to R. I am writing a function to (1) produce a sparse stochastic Gaussian 2D field and (2) perform a systematic transect sampling on this field, this carried out many times in a simulation framework. My function does a good job at producing the random field (a matrix of zeros and some manifestations of the stochastic process, depending on a parameter of the function determining how probable it is that t...
2009 Feb 12
0
Patch for src/main/character.c, systematizing recent fix to do_grep
The attached patch provides a modification to the recent fix/improvement to do_grep already included in the most recent development version. The original fix added new functionality to the grep function by adding a new parameter, 'invert'. In the source code for the underlying do_grep, the value of the parameter is used to invert the logical match-no match flag vector ind. The
2014 Apr 03
3
[LLVMdev] SIMD Projects with LLVM
...them (SSE2 Hoisting). We're not sure how much has been tried before, or even makes sense, but we're eager to learn. Briefly the projects are: SSE2 Hoisting: translating programs that directly use SSE2 intrinsics into platform-independent code expressed with LLVM IR. Long integer support: systematic support for i128, i256, ... targetting SIMD registers. Systematic strategies for the shufflevector operation. This is a very powerful operation that can be used to code for arbitrary rearrangement of data in SIMD registers. No architecture we know of supports it in its full generaility. Bu...
2006 Feb 07
0
lme and Assay data: Test for block effect when block is systematic - anova/summary goes wrong
Consider the Assay data where block, sample within block and dilut within block is random. This model can be fitted with (where I define Assay2 to get an ordinary data frame rather than a grouped data object): Assay2 <- as.data.frame(Assay) fm2<-lme(logDens~sample*dilut, data=Assay2, random=list(Block = pdBlocked(list(pdIdent(~1), pdIdent(~sample-1),pdIdent(~dilut-1))) )) Now, block
2008 Jul 27
2
Link functions in SEM
...would like to be able to do it in R, ofcourse. I have explored the 'sem' package from John Fox, but it does not seem to be able to fit non-linear relations. Is there some R-package or way to get this done? I have also considered creating a seperate latent variable in the sem model for the systematic component of the predictors, but then I still need a way to fix a non-linear link from the systematic component to the dichotomous Y variable. -- View this message in context: http://www.nabble.com/Link-functions-in-SEM-tp18679236p18679236.html Sent from the R help mailing list archive at Nabble....
2006 May 28
1
Systematic treatment of missing values
I am wondering whether there is a well-accepted approach to handling missing values (NA's) in a programming language such as R. For example, most functions seem to propagate NA to the output when the value of the missing entry could have mattered. In other words, most functions are not willing to "take a stand" on what the missing value was. However, some functions
2019 Mar 26
3
nbdkit design: varying the rate limit parameter
Hi Eric, We may have our first user (Tomas, CC'd) of the rate filter to limit NBD connections. As you recall it lets you do commands like: nbdkit --filter=rate memory size=64G rate=10M to limit network bandwidth to 10 Mbps. However a twist is that he needs to vary the parameter while nbdkit is running in response to a UI, and we haven't really thought about that before. In the
2002 Sep 10
1
Fw: Problem joing a W2KSP1 client to a Samba PDC (2.2.5).
The Virus controllers wouldn't let me send the attachment... ----- Original Message ----- From: "Trevor Fraser" <trevor@systematic.co.za> To: "Tommy Eriksson" <tommy.eriksson@ctakt.com> Cc: <samba@lists.samba.org> Sent: Tuesday, September 10, 2002 6:32 PM Subject: Re: [Samba] Problem joing a W2KSP1 client to a Samba PDC (2.2.5). > Hi Tommy. > > It's a ready to use patch. You just execut...
2009 Jan 22
3
how to study the lead and lag relation of two time series?
Hi all, Is there a way to study the lead and lag relation of two time series? Let's say I have two time series, At and Bt. Is there a systematic way of concluding whether it's A leading B or B leading A and by how much? Thanks!
2003 Mar 11
0
Time series application question
I am comparing the efficacy of two filtering techniques on a simulated time series that has random and systematic errors. As the data is simulated, I know the frequencies and amplitudes that generate the systematic noise. I'm looking for a way to compare the techniques in a simulation framework - i.e., I will generate many instances of the time series varying the parameters, perform the filtering, and test...
2008 Feb 25
0
how to find the significance F for one-way ANOVA
I am now writing an R code to do the systematic permutation test and the random permutation test. And I encountered a couple of problems which I cannot figure them out. At first, whenever I type "permtest" in my R2.6.1, it always shows:"there is no such a function", I tried again and again and eventually I found I h...
2010 Jan 28
1
Problem with R math library.
.... The interface documentation is here: http://yziquel.homelinux.org/topos/api/ocaml-r/Rmath.html For instance, for the norm_rand symbol, I have the following documentation comment: > val norm_rand : unit -> float > Random variates from the standard normal distribution. Bug: currently systematically returns -8.77332116900134373. Any idea as to why the function systematically returns the same value? Is there a way the math library should be initialised? All the best, -- Guillaume Yziquel http://yziquel.homelinux.org/
2017 Jun 30
20
[Bug 101665] New: lspci blocks forever with a GP107M
https://bugs.freedesktop.org/show_bug.cgi?id=101665 Bug ID: 101665 Summary: lspci blocks forever with a GP107M Product: xorg Version: unspecified Hardware: Other OS: All Status: NEW Severity: normal Priority: medium Component: Driver/nouveau Assignee: nouveau at
2012 Aug 15
2
sample() from (un-)sorted vectors
Hello, Vector y is an alphabetically sorted version of vector x. Will both samples, X and Y, be "absolutely" random or will they have systematic differences? And: Should I sort or shuffle a vector before sampling? Thank you, *S* x <- as.factor(LETTERS[sequence(10:1)]) y <- sort(x) X <- sample(x, 5) Y <- sample(y, 5) -- Sascha Vieweg, saschaview at gmail.com