similar to: piece wise functions

Hi R-helpers, I'm new to time series modelling, but my requirement seems to fall just outside the capabilities of the arima function in R. I'd like to fit an ARMA model where the variance of the disturbances is a function of some exogenous variable. So something like: Y_t = a_0 + a_1 * Y_(t-1) +...+ a_p * Y_(t-p) + b_1 * e_(t-1) +...+ b_q * e_(t-q) + e_t, where e_t ~ N(0, sigma^2_t),

Dear R people: Is there a way to perform simple polynomial multiplication; that is, something like (x - 3) * (x + 3) = x^2 - 9, please? I looked in poly and polyroot and expression. There used to be a package that had this, maybe? thanks, Erin -- Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: erinm.hodgess at

Dear R-Users, I need to find a smooth function f() and coefficients a_i that give the best fit to y ~ a_0 + a_1*f(x_1) + a_2*f(x_2) Note that it is the same non-linear transformation f() that is applied to both x_1 and x_2. So my first question is how can I do it in R? A more general question is this: suppose I have a utility function U(a_i, f()), where f() is say a spline. Is there a general

This came up in D20764, this IR verifies today: %X = type opaque define void @f_0(%X* %ptr) { %t = load %X, %X* %ptr ret void } define void @f_1(%X %val, %X* %ptr) { store %X %val, %X* %ptr ret void } which I found surprising -- what does it mean to load / store values of unknown sizes? Passing it to llc fails an assertion. Are there legitimate cases where we'd want to generate

Thanks for your answers. Another example of unsound transformation on Boolean algebra. According to the LLVM documentation (http://llvm.org/docs/LangRef.html#undefined-values) it is unsafe to consider ' a & undef = undef ' and ' a | undef = undef ' but 'undef xor undef = undef' is safe. Now, given an expression ((a & (~b)) | ((~a) & b)) where a and b are

To reiterate what I said on IRC, I agree with David and would expect the verifier to reject unsized loads and stores. On Mon, May 30, 2016 at 4:05 PM Sanjoy Das via llvm-dev < llvm-dev at lists.llvm.org> wrote: > This came up in D20764, this IR verifies today: > > %X = type opaque > > define void @f_0(%X* %ptr) { > %t = load %X, %X* %ptr > ret void > } > >

Dear all, I have two highly correlated variables (y and x), and both of them depend on a third variable (A, for Area). Multiple regression (y=a+(b*x)+(c*A)) would have collinearity problems, so I decided to do a partial regression to predict y. I did it this way: - I regressed y to A, and calculated the residuals (e_y) (reg1) - I regressed x to A, and calculated the residuals (e_x) (reg2)

Hello, I have a simulated data structure in which students are nested within teachers, and with each student are associated two test scores. There are 20 classrooms and 25 students per classroom, for a total of 500 students and two scores per student. Here are the first 10 lines of my dataframe "d": studid tchid Y time 1 1 1 -1.0833222 0 2 1 1

Hi, It is my understanding that the eigenvectors of a circulant matrix are given as follows: 1,omega,omega^2,....,omega^{p-1} where the matrix has dimension given by p x p and omega is one of p complex roots of unity. (See Bellman for an excellent discussion on this). The matrix created by the attached row and obtained using the following commands indicates no imaginary parts for the

Dear R users, I am a mathematics postdoc at UC Berkeley. I have written a package in a Computational Algebra System named Singular http://www.singular.uni-kl.de to compute the Maximum Likelihood of a given probability distribution over several discrete random variables. This package gives exact answers to the problem. But more importantly, it gives All MLE solutions. My understanding is that

When you say that distribution shouldn't be used, do you mean within instcombine rather than some other pass? Or not all as an IR optimization? A dedicated optimization pass that looks for and makes factoring/distribution folds to eliminate instructions seems like it would solve the problems that I'm seeing. Ie, I'm leaning towards the proposal here: https://reviews.llvm.org/D41574

* Kill the A8+A8 hack. Recent enough X servers (>=1.7) fall back to ARGB glyphs for drivers not supporting A8 render targets. * Kill all the global state. It doesn't matter a lot yet but it might if we get multicard working at some point. * Other random clean-ups with no functional changes. Some numbers from x11perf -aa10text -aa24text -comppixwin10 -comppixwin500: * Before, with A

> On May 8, 2018, at 9:50 AM, Daniel Berlin via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > 1. The reassociate pass that exists right now was *originally* (AFAIK) written to enable CSE/GVN to do better. Agreed. The original mindset included a (naive) belief that going with a canonical form was better than teaching redundancy elimination to handle abstractions (as a matter

Hello, I have a program called "Evidence Scribe" it runs with .NET Whenever I try to run it I receive this: Code: blake at blake-desktop ~ $ env WINEPREFIX="/home/blake/.wine" wine "C:\Program Files\Idoneum\Evidence Scribe\Evidence Scribe.exe" fixme:gdiplus:GdipGetFontHeightGivenDPI Unhandled unit type: 3 Unhandled Exception: System.InvalidOperationException:

Hi, could anyone tell me how predict() predicts the new value(s), of a MA(1) arima-modell. its really easy to make it with an AR(1), knowing the last term, but how can i or R know the last error? It would also help if somebody could tell me how to find the "open" source of the function predict(). Thanks and sorry for my poor english. -- View this message in context:

Can someone point me to the appropriate functions for fitting multiple statistical models that are coupled to each other. The data are measurements of salinity s and temperature t at stations id and pressures at p as well as surface elevations h at stations id. The problem is, for any new station, to estimate s at all p, given t at all p and given h. If h is ignored, the for each p, there

Hi Soham, You're right that in LLVM IR arithmetic (with the current definition of `undef`) is not distributive. You can't replace `A * (B + C)` with `A * B + A * C` in general, since (exactly as you said) for A = `undef`, B = `1`, C = `-1` the former always computes `0` while the latter computes `undef`. This is fundamentally because replacing `A * (B + C)` with `A * B + A * C`

I've installed ADAM interactive anatomy 4.0 on Ubuntu using wine 1.1.6 and winetricks to install dot net 1.1. ADAM is a dot net application. After installation and offline activation (online fails), the application starts, but gives the error: Code: System.MissingMethodException: Method not found: Int32 SkySoftware.FileViewControl.FileView.get_SelectedCount(). at a.a.c.a.a.h.b() at

Hi folks, I am having a question about efficiently finding the integrals of a list of functions. To be specific, here is a simple example showing my question. Suppose we have a function f defined by f<-function(x,y,z) c(x,y^2,z^3) Thus, f is actually corresponding to three uni-dimensional functions f_1(x)=x, f_2(y)=y^2 and f_3(z)=z^3. What I am looking for are the integrals of these three

Hola a todos: Tengo un problema con las fechas, básicamente necesito una diferencia en días y siempre se sale en segundos. Salvo un ejemplo copiado de un libro, pero yo necesito procesar los datos propios. Les paso el código en R (copiar y pegar, son solo dos días que se comparan) y al final como me salen los resultados porque es medio complicada mi redacción. ¿Alguna idea? fechas1