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  1. This forum is for questions related to the use of Apollo. We will answer some general choice modelling questions too, where appropriate, and time permitting. We cannot answer questions about how to estimate choice models with other software packages.
  2. There is a very detailed manual for Apollo available at http://www.ApolloChoiceModelling.com/manual.html. This contains detailed descriptions of the various Apollo functions, and numerous examples are available at http://www.ApolloChoiceModelling.com/examples.html. In addition, help files are available for all functions, using e.g. ?apollo_mnl
  3. Before asking a question on the forum, users are kindly requested to follow these steps:
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    3. Check the frequently asked questions section on the Apollo website, which discusses some common issues/failures. Please see http://www.apollochoicemodelling.com/faq.html
    4. Make sure that R is using the latest official release of Apollo.
  4. If the above steps do not resolve the issue, then users should follow these steps when posting a question:
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Search found 6 matches

by wulalala
30 Aug 2022, 00:43
Forum: Model estimation
Topic: version 0.2.7 and 0.2.1 generate different results
Replies: 9
Views: 7774

Re: version 0.2.7 and 0.2.1 generate different results

with currently how I applied weights, running a simple MNL model with only subset of the variables with v0.2.1 and 0.2.7 are shown below. The MNL and nested logit model are based on the same dataset, but the nested logit model break the alternative 3 into three sub alternatives:3, 30 and 31. running...
by wulalala
29 Aug 2022, 23:48
Forum: Model estimation
Topic: version 0.2.7 and 0.2.1 generate different results
Replies: 9
Views: 7774

Re: version 0.2.7 and 0.2.1 generate different results

what do you mean by "weights average to 1"? Just want to make sure I'm including weights properly before I try the MNL. Each observation has a weight. The value of weights ranges between 30 to 400. I specified the column of weights in apollo_control, and also have another line of P=apollo_...
by wulalala
29 Jul 2022, 23:41
Forum: Model estimation
Topic: version 0.2.7 and 0.2.1 generate different results
Replies: 9
Views: 7774

Re: version 0.2.7 and 0.2.1 generate different results

Hi, is it because I used sample weights so the starting LL is better than final LL? Is starting LL accounting weights?
by wulalala
25 Jul 2022, 02:54
Forum: Model estimation
Topic: version 0.2.7 and 0.2.1 generate different results
Replies: 9
Views: 7774

Re: version 0.2.7 and 0.2.1 generate different results

Thank you for the response. the code I used is: ### Clear memory rm(list = ls()) ### Load Apollo library library(apollo) library(reshape2) ### Initialise code apollo_initialise() ### Set core controls apollo_control = list( modelName ="Apollo_try_1", modelDescr ="NL_two_level on mode ...
by wulalala
15 Jul 2022, 18:34
Forum: Model estimation
Topic: version 0.2.7 and 0.2.1 generate different results
Replies: 9
Views: 7774

version 0.2.7 and 0.2.1 generate different results

Hi there, I ran a nested logit model on same dataset using same codes in version 0.2.1 and version 0.2.7. V0.2.1 generated meaningful results (i.e., significant estimates, logsum coefficient between 0 and 1, standard error with actual numbers as values), but V0.2.7 generated crazy results (i.e., sta...
by wulalala
22 Jan 2022, 00:51
Forum: Post-estimation analysis/use of results
Topic: prediction with weights
Replies: 1
Views: 2002

prediction with weights

I estimated a MNL model with weights (weights not equal to 1). Then, I'm hoping to apply the estimated model to the same dataset that I used in estimation, but got really wired output. What I did is simply using: predictions = apollo_predicition (model,apollo_probabilities, apollo_inputs) but got re...