similar to: Curve fitting, probably splines

Displaying 20 results from an estimated 11000 matches similar to: "Curve fitting, probably splines"

2005 Mar 30
6
French Curve
Dear R experts, Did someone implemented French Curve yet? Or can anyone point me some papers that I can follow to implement it? thanks in advance for your help. Paul
2012 Jul 11
2
Modifying the design matrix X in GAMS to suit data assimilation
I have a data assimilation problem that might be amenable to the use of GAMS, but I am not sure how feasible it is to implement. I was told the R mailing list was a great resource. My observations are spatiotemporal salinity in the San Francisco Bay at a number of instruments over a few days. The thing that I want to fit is the initial condition for a salt transport model at the beginning of this
2012 May 17
1
oldlogspline probabilities
I using oldlogspline (from logspline package) to model data distributions, and having a problem. My data are search area sizes. They are based on circular search radii from random points to the nearest edge of the nearest grass tussock. Search area sizes are distributed from 0 (the random point intercepts a tussock) and upwards (as points are further from any tussocks). The density of all my
2003 Jan 09
2
GAM with Thin plate splines
Hello, I'm a student at the University of Klagenfurt / Austria and I need some help ! I have to predict 24 daily load-values. Therefor I got a dataset with following colums: 24 past daily load-values 6 past daily temperature-values My goal is to find a model (GAM with thin plate splines) in R. I found the function "gam" in the R-library "mgcv", but it just fits
2005 Dec 12
2
Bivariate Splines in R
Hi.., is there a function in R to fit bivariate splines ? I came across 'polymars' (POLSPLINE) and 'mars' (mda) packages. Are these the one to use or are there other specific commands? Thanks. Harsh
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
2011 Jun 07
2
gam() (in mgcv) with multiple interactions
Hi! I'm learning mgcv, and reading Simon Wood's book on GAMs, as recommended to me earlier by some folks on this list. I've run into a question to which I can't find the answer in his book, so I'm hoping somebody here knows. My outcome variable is binary, so I'm doing a binomial fit with gam(). I have five independent variables, all continuous, all uniformly
2010 Dec 14
2
Use generalised additive model to plot curve
Readers, I have been reading 'the r book' by Crawley and think that the generalised additive model is appropriate for this problem. The package 'gam' was installed using the command (as root) install.package("gam") ... library(gam) > library(gam) Loading required package: splines Loading required package: akima > library(mgcv) This is mgcv 1.3-25 Attaching
2009 Jan 16
2
Smooth periodic splines
Hello group! Is there a package that allows to fit smooth *periodic* splines to data? I'm interested in a function which combines the functionality of smooth.spline and splines::periodicSpline. Thanks, Andrey
2010 Apr 02
4
Derivative of a smooth function
Dear All, I've been?searching for?appropriate codes to compute the rate of change and the curvature?of ?nonparametric regression model whish was denoted by a smooth function?but?unfortunately?don't manage to?do?it. I presume that such characteristics from a smooth curve can be determined by the first and second derivative operators. The following are the example of fitting a
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: >
2011 Mar 14
1
Help- Fitting a Thin Plate Spline
Hi Everyone, I'm a pretty useless r-er but have data that SPSS etc doesn't like. I've managed to do GLMs for my data, but now need to fit a thin plate spline for my data (arcsine.success~date.num:clutch.size) If anyone has a bit of spare time and could come up with a bit of code I'd be very grateful- I just don't get R language! Thanks Rach -- View this message in context:
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!
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
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
2006 Mar 16
1
running median and smoothing splines for robust surface f itting
loess() should be able to do robust 2D smoothing. There's no natural ordering in 2D, so defining running medians can be tricky. I seem to recall Prof. Koenker talked about some robust 2D smoothing method at useR! 2004, but can't remember if it's available in some packages. Andy From: Vladislav Petyuk > > Hi, > Are there any multidimenstional versions of runmed() and >
2003 Apr 07
3
spline with multiple predictor vars?
Hi, is there a way in R to generate a polynomial spline with multiple predictor variables? I have one response and two predictors and I'm trying to fit a spline model for this... Please cc me on the reply.. Thanks, nirmal
2011 Aug 06
1
How to estimate confidential intervals for the derivatives of cubic smoothing spline
Dear all, I want to use smooth.spline to construct a cubic smoothing spline and its first derivative to my data. However, the predict.smooth.spline does not seem to provide a SE for both the fitted values and their derivatives. How should I calculate it? Thank you very much, Bingzhang
2009 Oct 13
2
How to choose a proper smoothing spline in GAM of mgcv package?
Hi, there, I have 5 datasets. I would like to choose a basis spline with same knots in GAM function in order to obtain same basis function for 5 datasets. Moreover, the basis spline is used to for an interaction of two covarites. I used "cr" in one covariate, but it can only smooth w.r.t 1 covariate. Can anyone give me some suggestion about how to choose a proper smoothing spline
2007 Jul 02
1
gam function & time trend splines
I've been doing a simple time-series analysis looking at the relationship between daily pneumonia hospitalizations and daily temperature. To mimic some of the literature, I've been including a time-trend to try to account for normal cyclical trends in hospitalization. So I've been using a function that looks something like this: gam(pneucount ~ temp_f +