[Limdep Nlogit List] Help for a Limdep neophyte

[William Greene]

Mr. Edwards.  For the second logit model, you have to figure out what you
want to do with the other variables in the model - where to fix them - so
this applies to the first. If you want to plot it as a function of
BID, you should first find out what range to be plotting over. You might
do this:
BLOGIT ; LHS = YPAY ; RHS = one,bid $
CALC ; LowBid = Min(bid) ; HighBid = Max(bid) ; MedBid = Med(bid) 
     ; b1 = b(1) ; b2 = b(2) $
SAMPLE ; 1 $
FPLOT ; labels = Bids
      ; Limits=LowBid,HighBid
      ; Start  = MedBid
      ; Plot (Bids)
      ; Pts = 200
      ; Fcn = 1/(1+exp(b1 - b2*bids)) $
SAMPLE ; All $
This will plot the function values for the values in the range of
bids.  That said, I took your word for it that that was the function you
wanted, but it doesn't look right to me.  You have the wrong sign on
b2 in there.
/Bill Greene


----- Original Message -----
From: "Peter Edwards" <pedwards at UDel.Edu>
To: limdep at limdep.itls.usyd.edu.au
Sent: Saturday, September 15, 2007 1:35:25 PM (GMT-0500) Auto-Detected
Subject: [Limdep Nlogit List] Help for a Limdep neophyte

Hello,

I am NLOGIT newbie who is stumbling thru trying to figure out stuff.

I am analysing a set of Dichotomous choice data.   I have calculated WTP 
estmates etc.  Now I am trying to understand how to display some of the 
descriptive statistics. Also I am trying to figure out how to plot the PDF 
and CDF based on my estimation results.

for example from the basic estimation(s) below, how do I plot the Prob 
density function?
BLOGIT; LHS=YPAY; RHS=ONE,BID$

BLOGIT; LHS=YPAY; 
RHS=ONE,BID,TRPJAM,NIGHTS,PERS,AGE,FEM,AGESQ,HSCH,COLLGE,GRAD

I tried the following...but it is wrong....

FPLOT ; labels=(ypay)

;plot(ypay)

;limits=0,200

;start=0

;pts=100

;Fcn=1/(1+exp(b(1)-b(2)(bid)))$



I have been stumbling through the manuals but I have not been be able to get 
it right.

PETER EDWARDS



++++++++++++++++++++++++++++++++
Peter E.T. Edwards
PhD. Candidate
Graduate College of Marine Studies
Room 312 Robinson Hall
Newark, DE 19716
http://www.ocean.udel.edu/graduate/marpol/marpol.html




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-- 
Professor William Greene
Department of Economics
Stern School of Business
New York University
44 West 4th St., Rm. 7-78
New York, NY   10012
http://www.stern.nyu.edu/~wgreene
212.998.0876