similar to: Coefficient of determination for non-linear equations system (nlsystemfit)

Displaying 20 results from an estimated 1000 matches similar to: "Coefficient of determination for non-linear equations system (nlsystemfit)"

2006 Jan 12
1
Problem with NLSYSTEMFIT()
Hello, I want to solve a nonlinear 3SLS problem with "nlsystemfit()". The equations are of the form y_it = f_i(x,t,theta) The functions f_i(.) have to be formulated as R-functions. When invoking "nlsystemfit()" I get the error Error in deriv.formula(eqns[[i]], names(parmnames)) : Function 'f1' is not in the derivatives table
2011 Mar 10
2
R beginner - Error in as.vector(x, mode)
Hi everyone, I am new to R and keep getting the message Error in as.vector(x, mode) while trying to run nlsystemfit. Below is my exact code. The data is in Stata format because I only recently swapped to R and am trying to compare results from Stata to make sure I know what is going on. I have searched google and read sever R-help articles with this error. They all say the problem is to do
2008 Oct 10
2
linear expenditure model
Hi, I would like to estimate a linear expendire with Systemfit package. (method: "SUR") As someone could show me how to define the equations? Thanks. -- Think before you print ! ********************************************************************** Disclaimer: This e-mail may contain confidential informa...{{dropped:9}}
2010 Jan 09
2
Functions for QUAIDS and nonlinear SUR?
Hi, I would like to estimate a quadratic almost ideal demand system in R which is estimated usually by nonlinear seemingly unrelated regression. But there is no such function in R yet but it is readily available in STATA (nlsur), see B. Poi (2008): Demand-system estimation: Update, Stata Journal 8(4). Now I am thinking, what is quicker learning to "program" STATA which seems not really
2011 Nov 15
1
Estimating model parameters for system of equations
Hi all, I'm trying to estimate model parameters in R for a pretty simple system of equations, but I'm having trouble. Here is the system of equations (all derivatives): eqAlgae <- (u_Amax * C_A) * (1 - (Q_Amin / Q_A)) eqQuota <- (p_max * R_V) / (K_p + R_V) - ((Q_A-Q_Amin)*u_Amax) eqResource <- -C_A * (p_max * R_V) / (K_p + R_V) eqSystem <- list(C_A = eqAlgae, Q_A = eqQuota,
2008 Nov 06
2
How to return individual equation from {aidsEst} in package [micEcon]?
Hi, R core team I am using the function {aidsEst} in package [micEcon] to do an AIDS model now. So far, everything is good. But I want to test the auto correlation and heteroskedasticity of the individual equation from AIDS demand system. How can I return the individual equation? PS: serial correlation test is {bgtest} in package [lmtest] and heteroskedasticity is {bptest} in package
2007 Mar 28
0
nlsystemfit: Errors with reproducing the manual example
Hi everybody, I'm a newbye with lots of problems :). I'm trying to use nlsystemfit, but I recieve two error messages whose origin that I don't understand. 1) When I try to reproduce the example reported in the systemfit package manual, that is library( systemfit ) data( ppine ) hg.formula <- hg ~ exp( h0 + h1*log(tht) + h2*tht^2 + h3*elev + h4*cr) dg.formula <- dg ~ exp( d0
2008 Nov 20
1
Nonlinear restrictions in systemfit
Hey, I want to implement a structural model with the package systemfit with some linear and nonlinear constraints. How to implement linear restrictions is clear. Does anybody know how to set up nonlinear restrictions in the systemfit packages. For example: beta1 = beta2-(beta4/beta6) I look forward to your reply -- View this message in context:
2008 Apr 25
5
Non-linear system of equations
Hello R users, I am trying to estimate the parameters of a bimodal normal distribution using moments matching, so I have to solve a non-linear system of equations. How can I solve the following simple example? x^2 - y^2 = 6 x ? y = 3 I heard about nlsystemfit, but I don?t know how to run it exactly. I have tried the following code, but it doesn?t really work: f1 <-y~ x[1]^2-x[2]^2-6 f2
2003 Oct 17
2
nlm, hessian, and derivatives in obj function?
I've been working on a new package and I have a few questions regarding the behaviour of the nlm function. I've been (for better or worse) using the nlm function to fit a linear model without suppling the hessian or gradient attributes in the objective function. I'm curious as to why the nlm requires 31 iterations (for the linear model), and then it doesn't work when I try to add
2009 Aug 18
3
R formula
Hi I was trying to estimate simultaneous equation system in R using systemfit. I used the following commands >library(systemfit) > data(Kmenta) > attach(Kmenta) >eqDemand<-consump~price+income > eqSupply<-consump~price+farmprice+trend > fitsur<-systemfit("SUR",list(demand=eqDemand, supply=eqSupply)) and got the following error messege Error in
2009 Jul 23
2
SystemFit
Hi, I have two products which are substitudes. I try to fix a system as below to mydata. Demand1 = A1 -B1*Price1 + C1*Price2 Demand2 = A2 +B2*Price1 - C2*Price2 I would expect C1 & B2 to be symmetric, If they are truly substitude. How can I enforce this symmetry when creating a system of equations via SystemFit ? -- View this message in context:
2012 Oct 17
1
extracting and restricting coefficients
Hi  I want to fit two equations simultaneously EQ1<-Y1~X1+X2 EQ2<-Y2~X1+X2 eqsystem<-list(Y1HAT=EQ1,Y2HAT=EQ2) fitols<-systemfit(eqsystem, method="OLS", data=BB) How do I get coefficients for the first equation? R code How do I restrict coefficient of X2 in the first equation (say , restrict it to less than  zero). R code Your help is appreciated. Dereje [[alternative
2004 Jan 20
2
Error: unknown identifier {|} in tabular format {|l|c|c|c|}
I've got a package I would like to send out for testing and have noticed a "problem" with the \tabular portion of the help "compiler" the code for inserting vertical lines, in the tabular environment, causes the build to choke, but not the check command. C:\>rcmd build --binary -docs=all nlsystemfit \tabular{|l|c|c|c|}{ \hline Method \tab Instruments \tab
2012 Apr 07
1
Systemfit with structural equations and cross equation parameter interaction
Hi there, I want to estimate simultaneous equation model with panel data. The model looks as follows Y1=a0+a1*X1+a2*X2 Y2=b0+b1*X2+b2*X1 X1=Z1-(Y1/a1) X2=Z2-(Y2/b1) I In this model Y1, Y2, X1 and X2 are endogenous variables; Z1, Z2 are exogenous variables and a0, a1, a2, b0, b1 and b2 are parameters. Could any one please help me how to estimate this model in R. Thanking you in anticipation
2010 Sep 02
3
Simultaneous equations
Dear all, I am relatively new to R and have had some difficulty in understanding the user manual for a package that I have downloaded to evaluate non-linear simultaneous equations. The package is called systemfit. Does anyone have any experience of this package? What I am trying to do is solve a non linear simultaneous equations... Could anyone give me an example (please) of the code that
2011 Mar 14
0
nlysystemfit and loglikelihood values
Dear R-help, The documentation for systemfit shows that logLik() can be used to obtain loglikelihood values from linear systems estimated by systemfit(). It seems to me that logLik() cannot be used for nlsystemfit(). Does anyone know of any other packages that might let me obtain the loglikelihood of a model estimated with nlsystemfit()? Kind regards, Alex Olssen
2009 Feb 20
2
System of logistics Equations
Hi R-masters I need yours help about a problema in one of may ongoing researchers. In my research the subjects (20 in total) answer 60 questions (20 type G, 20 type S and 20 type P). Which questions is classified about 3 factor (2 level each) and the subject score with 2 scale (not integer value is possible but rare): Val range -7 to 7 and other Car range 1 to 7. This a code to fake database
2012 Mar 21
1
How to do 2SLS in R
Hi List I want to carry out structural mode. Following Example l have taken from Basic Econometrics- Damodar Gujarati : Advertising intensity function: Ad/S = a0 + a1M + a2 (CD/S) + a3C + a4C2 + a5Gr + a6Dur – (1) Concentration function: C = b0 + b1 (Ad/S) + b2 (MES/S) -(2) Price-cost margin function: M = c0 + c1(K/S) + c2Gr + c3C + c4GD + c5(Ad/S) + c6 (MES/S)
2008 Jun 03
3
How to solve a non-linear system of equations using R
Dear R-list members, I've had a hard time trying to solve a non-linear system (nls) of equations which structure for the equation i, i=1,...,4, is as follows: f_i(d_1,d_2,d_3,d_4)-k_i(l,m,s) = 0 (1) In the expression above, both f_i and k_i are known functions and l, m and s are known constants. I would like to estimate the vector d=(d_1,d_2,d_3,d_4) which is solution