similar to: piecewise linear regression

Displaying 20 results from an estimated 6000 matches similar to: "piecewise linear regression"

2006 Apr 23
4
Penalties of using an eval on every request
Hello RoR! I''m building a rails app for hosting multi-page surveys. I set up questionnaire, question, and question_component models. Now I''m initializing them with some data. survey.rb q1 = Question.new "q1" q1.quote "Welcome to a test of the new interviewing system." q2 = Question.new "q2" q2.quote "Do you like pie?"
2010 Jan 07
0
piecewise regression using nlme function
Is a 95% CI on a breakpoint fixed effect legitimate when the nonlinear equation is continuous but not differentiable at the breakpoint? I used the nlme to generate a non-linear mixed-effects piecewise model with initial slope zero prior to an unknown breakpoint. It did give a 95% CI for the breakpoint. Thanks Erik whole model is complex, but here is the simple equation used:
2008 Dec 11
4
A package to set up a questionnaire & enter data
Hi R users, Is there a Package in R to - set up a questionnaire? - enter data? Best regards -- View this message in context: http://www.nabble.com/A-package-to-set-up-a-questionnaire---enter-data-tp20947237p20947237.html Sent from the R help mailing list archive at Nabble.com.
2012 Jun 02
1
Compare data between two groups/countries on 5-point Likert scale questionnare?
Hi everyone, I'm stuck on my dissertation which is due next week. I'm a business major student and my project is a comparative research on corporate social responsibility (CSR) between Chinese and German firms. According to my literature review, it's quite obvious that German firms have much better CSR initiatives and strategies than the Chinese ones and I wanted to test whether it was
2009 Mar 07
2
piecewise linear regression
Hi - I'd like to construct and plot the percents by year in a small data set (d) that has values between 1988 and 2007. I'd like to have a breakpoint (buy no discontinuity) at 1996. Is there a better way to do this than in the code below? > d year percent se 1 1988 30.6 0.32 2 1989 31.5 0.31 3 1990 30.9 0.30 4 1991 30.6 0.28 5 1992 29.3 0.25 6 1994 30.3
2005 May 30
3
Piecewise Linear Regression
Hi, I need to fit a piecewise linear regression. x = c(6.25,6.25,12.50,12.50,18.75,25.00,25.00,25.00,31.25,31.25,37.50,37.50,50.00,50.00,62.50,62.50,75.00,75.00,75.00,100.00,100.00) y = c(0.328,0.395,0.321,0.239,0.282,0.230,0.273,0.347,0.211,0.210,0.259,0.186,0.301,0.270,0.252,0.247,0.277,0.229,0.225,0.168,0.202) there are two change points. so the fitted curve should look like \ \ /\
2010 Feb 24
1
Remove missing observations
Hi everyone I have the following problem: My dataframe has 3 variables: ID, Year and and an outcome variable. The dataframe contains repeated measurements because the subjects filled out a questionnaire every year. The time span covers 2 years. Now I want to check if there is a significant change in the outcome over the 2 years with a paired wilcox.test. The problem: Not every subject
2006 Dec 02
1
Is there a better way for inputing data manually?
Dear All, I have worked with R for some time. It's a great tool for data analysis. But it's too hard to inputing raw data manually with R (I don't mean importing data. R is good at importing data). Maybe it's not a focused topic in this list, but I don't know other place where I can ask the question. How do you do when inputing data from a paper material, such as
2009 Mar 29
2
h exten no getting run ...
Asterisk 1.4 r181990 given the dialplan snippet below, can anyone tell me why the h exten is not being run ? ============================================================================ console output: [Mar 29 10:33:49] -- Executing [s at questionnaire-menu:1] Set("Zap/1-1", "TIMEOUT(digit)=3") in new stack [Mar 29 10:33:49] -- Digit timeout set to 3 [Mar 29
2007 Jul 29
1
Piecewise Regression with a known slope
Hey, all. I'm working on a data set with a broken stick linear regression where I know one of the two slopes. It is a negative linear function until the line intersects with the x-axis, at which point it becomes 0. It is not a nonlinear asymptotic function, and, indeed, using negative exponential or logistic types of fits as an approximation has tended to lead to an under or
2007 Aug 30
3
piecewise linear approximation
Dear list, I have a series of data points which I want to approximate with exactly two linear functions. I would like to choose the intervals so that the total deviation from my fitted lines is minimal. How do I best do this? Thanks! Kamila The information transmitted in this electronic communication...{{dropped}}
2024 Jul 26
1
Automatic Knot selection in Piecewise linear splines
dear all, I apologize for my delay in replying you. Here my contribution, maybe just for completeness: Similar to "earth", "segmented" also fits piecewise linear relationships with the number of breakpoints being selected by the AIC or BIC (recommended). #code (example and code from Martin Maechler previous email) library(segmented) o<-selgmented(y, ~x, Kmax=20,
2007 Feb 25
1
Repeated measures logistic regression
Dear all, I'm struggling to find the best (set of?) function(s) to do repeated measures logistic regression on some data from a psychology experiment. An artificial version of the data I've got is as follows. Firstly, each participant filled in a questionnaire, the result of which is a score. > questionnaire ID Score 1 1 6 2 2 5 3 3 6 4 4 2 ...
2024 Jul 16
2
Automatic Knot selection in Piecewise linear splines
>>>>> Anupam Tyagi >>>>> on Tue, 9 Jul 2024 16:16:43 +0530 writes: > How can I do automatic knot selection while fitting piecewise linear > splines to two variables x and y? Which package to use to do it simply? I > also want to visualize the splines (and the scatter plot) with a graph. > Anupam NB: linear splines, i.e. piecewise
2011 Oct 09
1
help with using last observation carried forward analysis for a clinical trial please
Hi, I have a series of id's with multiple visits and questionnaire scores. This is a clinical trial that will be analyzed using the last observation carried forward method. In other words, in order to comply with intent to treat analysis when many subjects withdraw, data points for the last visit must be generated and filled in with the last observation. The ultimate goal is to tabulate the
2012 Apr 05
1
how to do piecewise linear regression in R?
Dear all, I want to do piecewise CAPM linear regression in R: RRiskArb−Rf = (1−δ)[αMktLow+βMktLow(RMkt−Rf)] + δ[αMkt High +βMkt High(RMkt −Rf )] where δ is a dummy variable if the excess return on the value-weighted CRSP index is above a threshold level and zero otherwise. and at the same time add the restriction: αMkt Low + βMkt Low · Threshold = αMkt High + βMkt High · Threshold to ensure
2000 Jul 27
1
Interpolation using a piecewise linear function in higher dimensions
Dear all, I am just wondering if anybody has implemented a function that can give a piecewise linear interpolation in more than 2 dimensions? I have looked at the akima package, but I would rather like a piecewise linear interpolation rather than a spline and while it did the job quite satisfactory for 2 dimensions, I need to interpolate in at least three dimensions. If anybody has implemented
2007 Nov 14
0
Piecewise Linear Regression
Hi, Let me pick up this old thread. How does one extract the locations of the knots (ends of the segments) from the fit object below? Thanks, Vadim >From : roger koenker < roger_at_ysidro.econ.uiuc.edu > Date : Tue 31 May 2005 - 10:23:19 EST It is conventional to fit piecewise linear models by assuming Gaussian error and using least squares methods, but one can argue that
2008 Mar 24
0
What is the correct model formula for the results of piecewise linear function?
Dear friends, I used the B-spline (degree=1) method to fit the piecewise linear function and the results are listed below. m.glm<-glm(mark~x+poly(elevation,2)+bs(distance,degree=1,knots=c(16.13,24)) +bs(y,degree=1,knots=c(-0.4357,-0.3202 )),family=binomial(logit),data=point) summary(m.glm) Coefficients: Estimate Std.
2011 Mar 18
1
PREDICTIONS from a PIECEWISE LINEAR (mixed) MODEL: THEY AIN'T LINEAR BETWEEN BREAK POINTS!!
I Dears, if that wouldn't take u too much effort I'd like to ask for a swift opinion: I have a alinear (mixed effect) model that I wish to run as a piecewise one. When I predict the values Iget quite some odds and disturbing results: The predicted stright line after the break point is not straight at all, instead behaves like if it was a hig order polynomial or something similar!!!! I