similar to: Predicted points in splines

Displaying 20 results from an estimated 9000 matches similar to: "Predicted points in splines"

2012 Jun 05
1
Do YOU know an equation for splines (ns)?
Hi, I am looking at the change in N concentration in plant roots over 4 time points and I have fit a spline to the data using ns and lme: fit10 <- lme( N~ns(day, 3), data = rcn10G) I may want to adjust the model a little bit, but for now, let's assume it's good. I get output for the fixed effects: Fixed: N ~ ns(day, 3) (Intercept) ns(day, 3)1 ns(day, 3)2 ns(day, 3)3
2011 Feb 05
3
spline interpolation
Hello R-help I have the following data for a standard curve concentration(nM),fluorescence 0,48.34 2,58.69 5,70.83 10,94.73 20,190.8 50,436.0 100, 957.9   (1)Is there function in R to plot a spline. (2)How can I interpolation,say 1000 point from 0nM-100nM and store this as a data frame of concentration,fluorescence (3)How can I modify the code below so that instead of retrieving a concentration
2011 Sep 20
2
Multivariate spline regression and predicted values
Hello, I am trying to estimate a multivariate regression of Y on X with regression splines. Y is (nx1), and X is (nxd), with d>1. I assume the data is generated by some unknown regression function f(X), as in Y = f(X) + u, where u is some well-behaved regression error. I want to estimate f(X) via regression splines (tensor product splines). Then, I want to get the predicted values for some new
2012 May 31
0
splines and ns equation
Hi, I am looking at the change in N concentration in plant roots over 4 time points and I have fit a spline to the data using ns and lme: fit10 <- lme( N~ns(day, 3), data = rcn10G) I may want to adjust the model a little bit, but for now, let's assume it's good. I get output for the fixed effects: Fixed: N ~ ns(day, 3) (Intercept) ns(day, 3)1 ns(day, 3)2 ns(day, 3)3 1.15676524
2010 Apr 19
0
Natural cubic splines produced by smooth.Pspline and predict function in the package "pspline"
Hello, I am using R and the smooth.Pspline function in the pspline package to smooth some data by using natural cubic splines. After fitting a sufficiently smooth spline using the following call: (ps=smooth.Pspline(x,y,norder=2,spar=0.8,method=1) [the values of x are age in years from 1 to 100] I tried to check that R in fact had fitted a natural cubic spline by checking that the resulting
2011 Jan 20
1
Inverse Prediction with splines
Hello, I have fit a simple spline model to the following data. Data x y 0 1.298 2 0.605 3 0.507 4 0.399 5 0.281 6 0.203 7 0.150 8 0.101 Model Sp.1=lm(y~bs(x,df=4)) Now I wish to inverse predict the x for y=.75, say. Optimize works fine for a polynomial but I can figure out how to get the spline model into the function argument. Can anyone help me out. Thanks!! Jeff Jeff Morris Sanofi
2008 Dec 16
1
Application b-spline basis for polynomial splines
Hai everbody,  Is there anyone have simple application b-spline in r language? I need it for make me understanding about b-spline for polynomial spline. thank u Arif  New Email addresses available on Yahoo! Get the Email name you&#39;ve always wanted on the new @ymail and @rocketmail. Hurry before someone else does! [[alternative HTML version deleted]]
2006 Nov 07
1
multivariate splines
Hi, I am looking for an R package that would calculate multivarite (mostly 2d and 3d, tensor) cubic interpolating splines, so that I could evaluate these splines (and their derivatives) at many points (unkown at the time of calculating the spline polynomials) repeatedly. To make things concrete, I have an array V with dim(V) = k and gridpoint vectors grid=list(...), length(grid[[i]])==k[i],
2010 May 11
1
Splines under tension
Does anyone know if R has a function for splines under tension. I know there are numerous packages for spline interpolation within R i just can't find one that lets you determine the tension factor. Any help would be much appreciated! Sam -- View this message in context: http://r.789695.n4.nabble.com/Splines-under-tension-tp2173887p2173887.html Sent from the R help mailing list archive at
2004 Apr 09
2
Regression models w/ splines
Hi - I am fitting various Cox PH models with spline predictors. After fitting the model, I would like to use termplot() to examine the functional form of the fitted model (e.g., to obtain a plot of the relative risk (or log r.r.) versus the predictors). When there is only 1 predictor in the model, termplot returns a "?". In this case, I have not been able to figure out how to create
2010 Dec 08
1
I want to get smoothed splines by using the class gam
Hi all, I try to interpolate a data set in the form: time Erg 0.000000 48.650000 1.500000 56.080000 3.000000 38.330000 4.500000 49.650000 6.000000 61.390000 7.500000 51.250000 9.000000 50.450000 10.500000 55.110000 12.000000 61.120000 18.000000 61.260000 24.000000 62.670000 36.000000 63.670000 48.000000 74.880000 I want to get smoothed splines by using the class gam The first way I tried , was
2006 Jun 24
2
smoothing splines and degrees of freedom
Hi, If I set df=2 in my smooth.spline function, is that equivalent to running a linear regression through my data? It appears that df=# of data points gives the interpolating spline and that df = 2 gives the linear regression, but I just want to confirm this. Thank you, Steven
2007 Oct 05
2
Splines
I want to fit a cubic spline of x on y. where : x [1] 467 468 460 460 450 432 419 420 423 423 y [1] 1 2 3 4 5 6 7 8 9 10 using the syntax spline(y, x) I got following output : $x [1] 1.000000 1.310345 1.620690 1.931034 2.241379 2.551724 2.862069 [8] 3.172414 3.482759 3.793103 4.103448 4.413793 4.724138 5.034483 [15] 5.344828 5.655172
2002 May 02
1
splines
I've got a problem with the R function spline.des. I use the following arguments: x_seq(0,1,length=200) knot_quantile(x,(1:8)/9) ord_3 k_sort(c(rep(range(x),ord,knot))) derivs_rep(2,200) When I do spline.des(k,x,ord,derivs)$design on Splus and on R, I don't have the same results. However, if I take an order ord=4 (ie a spline of degree 3), then, I have the same
2011 Jul 19
2
Incorrect degrees of freedom for splines using GAMM4?
Hello, I'm running mixed models in GAMM4 with 2 (non-nested) random intercepts and I want to include a spline term for one of my exposure variables. However, when I include a spline term, I always get reported degrees of freedom of less than 1, even when I know that my spline is using more than 1 degree of freedom. For example, here is the code for my model: >
2009 Jul 05
2
integrar resultado de splines cubicos
hola soy nuevo usuario de R y necesito crear un objeto p tal que, p=lambda*integral[f´´(x)^2 dx ] donde "lambda" es uno de los parametros que resultan de la funcion "smooth.spline()" y la integral es sobre la derivada 2 de esa misma funcion... dos cuestiones: 1) como extraigo lambda de los resultados de smooth.spline() para usarlo como objeto cuando lo requiera y 2) como
2013 Apr 23
1
GAM Penalised Splines - Intercept
Hey all, I'm using the gam() function inside the mgcv package to fit a penalised spline to some data. However, I don't quite understand what exactly the intercept it includes by default is / how to interpret it. Ideally I'd like to understand what the intercept is in terms of the B-Spline and/or truncated power series basis representation. Thanks!
2000 Sep 04
2
bug in spline()? (PR#653)
BUG IN SPLINE()? Version R-1.0.1, system i486,linux If the spline(x,y,method="natural") function is given values outside the range of the data, it does not give a warning. Moreover, the extrapolated value reported is not the ordinate of the natural spline defined by (x,y). Example. Let x <- c(2,5,8,10) and y <- c(1.2266,-1.7606,-0.5051,1.0390). Then interpolate/extrapolate with
2012 Jan 09
1
What is the function for "smoothing splines with the smoothing parameter selected by generalized maximum likelihood?
Dear all, I am new to R, and I am a biotechnologist, I want to fit a smoothing spline with smoothing parameter selected by generalized maximum likelihood. I was wondering what function implement this, and, if possible how I can find the fitted results for a certain point (or predict from the fitted spline if this is the correct language) -- View this message in context:
2008 May 01
1
Optimal knot locations for splines
Suppose I have two variables, x and y. For a fixed number of knots, I want to create a spline transformation of x such that a loss function is minimized. Presumably, this loss function would be least squares, i.e. sum (f(x)-y)^2. The spline transformations would be linear, quadratic or cubic. I know I can solve this problem using some optimization function in R, but I was wondering if anyone