No problem.
There are 4 models. Each has a dependent variable that may exist in the other 4 models. To solve this issue we incorporate a mixed logit model to account for their errors. So they are not independent and independent within the same model.
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Search found 14 matches
- 25 Apr 2023, 13:17
- Forum: Errors during model validation and/or estimation.
- Topic: Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
- Replies: 9
- Views: 1937
- 02 Feb 2023, 15:11
- Forum: Errors during model validation and/or estimation.
- Topic: Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
- Replies: 9
- Views: 1937
Re: Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
The 4 models each has a dependent variables. Each of the 4 model uses the other models' dependent variables as independent variables. This is why the mixed logit is done. Since not all of these were significant, in some of these models, one or more variables are omitted. Could the error be that I al...
- 20 Jan 2023, 16:37
- Forum: Errors during model validation and/or estimation.
- Topic: Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
- Replies: 9
- Views: 1937
- 19 Jan 2023, 15:18
- Forum: Errors during model validation and/or estimation.
- Topic: Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
- Replies: 9
- Views: 1937
Re: Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
To rephrase my last message. It worked in the sense that it is not producing an error, but all my t-ratios and p-values are NaN now.
Could you tell me if it's a problem with the data or a problem with the code?
Could you tell me if it's a problem with the data or a problem with the code?
- 16 Jan 2023, 16:39
- Forum: Errors during model validation and/or estimation.
- Topic: Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
- Replies: 9
- Views: 1937
Getting error: Error in maxOptim(fn=fn, grad=grad, hess=hess, start=start, method="BFGS",:NA in the initial gradient
I get the error: Error in maxOptim(fn = fn, grad = grad, hess = hess, start = start, method = "BFGS", : NA in the initial gradient In addition: There were 26 warnings (use warnings() to see them) When running my model. I could not find any google answers to solve it. Any help would be grea...
- 05 Jan 2023, 15:04
- Forum: Model specification
- Topic: Error when compiling utility function into a variable
- Replies: 1
- Views: 3242
Error when compiling utility function into a variable
I have this code below that works: library(apollo) library(haven) library(plyr) library(dplyr) library(labelled) library(tidyverse) randstad <- c( #b_randstad_is = 0, b_randstad_not = 0, b_randstad_to = 0, b_randstad_from = 0 ) wdist <- c( b_weekdist_dec = 0, b_weekdist_inc = 0, b_weekdist_same = 0,...
- 14 Dec 2022, 17:21
- Forum: Model specification
- Topic: More efficient way of doing a step-wise approach?
- Replies: 1
- Views: 840
More efficient way of doing a step-wise approach?
I have a model with a lot of dummy variables. There are about 6 control variables - each with on average 5 dummies. the 6 control variables leaves 63 combinations of models. My process right now would look like commenting off each variable individually and running the model. Is there any way to auto...
- 11 Aug 2022, 13:45
- Forum: Errors during model validation and/or estimation.
- Topic: Error when using mixed logit with only one observation per individual
- Replies: 6
- Views: 2870
Re: Error when using mixed logit with only one observation per individual
Got it to work. Solution confirmed.
- 10 Aug 2022, 16:17
- Forum: Errors during model validation and/or estimation.
- Topic: Error when using mixed logit with only one observation per individual
- Replies: 6
- Views: 2870
Re: Error when using mixed logit with only one observation per individual
What goes into that call? And where do I add it?
- 09 Aug 2022, 14:29
- Forum: Errors during model validation and/or estimation.
- Topic: Error when using mixed logit with only one observation per individual
- Replies: 6
- Views: 2870
Error when using mixed logit with only one observation per individual
Hello I am trying to build a mixed ordered logit model with a random error term. This is my model: #### nautos #### # ################################################################# # #### LOAD LIBRARY AND DEFINE CORE SETTINGS #### # ################################################################...