search for: a_p

...at. I have a multidimensional piece-wise regression linear problem, i.e. to find not only the regression coefficients for each "interval" but also the beginning and ends of the intervals. To simplify it to the one dimensional case and two intervals, the problem is to find A_0, A_1, ... A_p and "C" from the given sample, assuming the curve is like this: A_0*f_0(x)+A_1*f_1(x)+ ... + A_p*f_p(x) with x < C A_0'*f_0(x)+A_1'*f_1(x)+ ... + A_p'*f_p(x) with x >= C Functions f_1, f_2, ... f_p are known. Is there anything in R for that? I have tried to use nonl...

...(p to indicate pressure) depends on s,t, and p, and h is essentially a sum over the volume at each p. When the individual models are computed, coefficients should be chosen so that this is satisfied. How to do this in R? Without the coupling the least-squares formulation would seek coefficients a_p and b_p to minimize: sum_p(sum_p((s_id,p - a_p t_id,p + b_k)^2)). Minimization at each p is independent. With coupling, there would be an additional term: sum_id((sum_p(vp)-h_id)^2) where vp is a function of a_p t_id,p + b_k and of t_id. The functions for vp are nonlinear, but if necessary w...

Dear R-listers, I have to explain "y", a continous variable, with two variables "t" and "p" which are "factor variables": t is [1:12] and p is [1:18] (a value for y for each combination t*p). OK, then I try to adjust models like: y=a_p + b*t (I mean as many intercepts as levels of p) or y=a_p + b_p*t (as many intercepts and coefficients for t as levels of p). How is it possible to do that with GLM? other package? Thank you for advance, best regards, EASauleau. ============================================ Erik-Andr? SAULEAU SE...

...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), and with the variance specified by something like sigma^2_t = exp(beta_t * X_t), where X_t is my exogenous variable. I would be very grateful if somebody could point me in the direction of a library that could f...

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

...$msg = fgets($stdin,1024); fputs($stdlog,$msg . "\n"); ?> Extensions.conf: exten => 4343,1,Answer exten => 4343,2,AGI(example.php) exten => 4343,3,Busy AGI Debug: AGI Rx << SAY PHONETIC "abc" "#" -- Playing 'phonetic/a_p' (language 'en') -- Playing 'phonetic/b_p' (language 'en') -- Playing 'phonetic/c_p' (language 'en') -- AGI Script example.php completed, returning 0 -- Executing Busy("SIP/4321-081b9498", "") in new stack...

...$msg = fgets($stdin,1024); fputs($stdlog,$msg . "\n"); ?> Extensions.conf: exten => 4343,1,Answer exten => 4343,2,AGI(example.php) exten => 4343,3,Busy AGI Debug: AGI Rx << SAY PHONETIC "abc" "#" -- Playing 'phonetic/a_p' (language 'en') -- Playing 'phonetic/b_p' (language 'en') -- Playing 'phonetic/c_p' (language 'en') -- AGI Script example.php completed, returning 0 -- Executing Busy("SIP/4321-081b9498", "") in new stack...

...ct buf *) 0x0 nbp = (struct buf *) 0xc032d23c s = -1 error = 0 wait = 0 passes = 4 skipmeta = 0 lbn = 36 #10 0xc024b04b in ffs_sync (mp=0xc230e600, waitfor=2, cred=0xc145e900, p=0xc039b3e0) at vnode_if.h:558 a = {a_desc = 0xc032db40, a_vp = 0xdb241380, a_cred = 0xc145e900, a_waitfor = 2, a_p = 0xc039b3e0} vp = (struct vnode *) 0xdb241380 cred = (struct ucred *) 0xc145e900 waitfor = 2 p = (struct proc *) 0xc039b3e0 p = (struct proc *) 0xc039b3e0 nvp = (struct vnode *) 0xdb240f00 vp = (struct vnode *) 0xdb241380 ip = (struct inode *) 0x0 ump = (struct ufsmount *) 0xc230e400 fs...