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Search found 11 matches

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by jbas
14 Oct 2024, 09:13
Forum: Model estimation
Topic: Signs of coefficients are complete opposite
Replies: 9
Views: 111720

Re: Signs of coefficients are complete opposite

Stephane, sorry for the late reply. Sure, here are the shares by LOS.

If I'm reading the tables correctly, the mean value of the LOS were, almost in all cases, lower, when the chosen alternative was the Premium or Superior one. Which is precisely the opposite of what should be happening... This is ...
by jbas
03 Oct 2024, 09:41
Forum: Model estimation
Topic: Signs of coefficients are complete opposite
Replies: 9
Views: 111720

Re: Signs of coefficients are complete opposite

Stephane, you were right, importing a csv solved it.

The result of applying


choiceAnalysis_settings <- list(
alternatives = c(basic=1, premium=2, superior=3, none=4),
avail = list(basic = database$av_basic, premium = database$av_premium, superior = database$av_superior, none = database$av_none ...
by jbas
30 Sep 2024, 14:22
Forum: Model estimation
Topic: Signs of coefficients are complete opposite
Replies: 9
Views: 111720

Re: Signs of coefficients are complete opposite

I'm trying to do so....


choiceAnalysis_settings <- list(
alternatives = c(basic=1, premium=2, superior=3, none=4),
avail = list(basic = database$av_basic, premium = database$av_premium, superior = database$av_superior, none = database$av_none),
choiceVar = database$CHOICE,
explanators ...
by jbas
30 Sep 2024, 11:23
Forum: Model estimation
Topic: Signs of coefficients are complete opposite
Replies: 9
Views: 111720

Re: Signs of coefficients are complete opposite

Thanks, Stephane, for your reply.

Let me copy below choice shares, and choice by cost. Regarding the latter, there is a high variety of prices since they have been calculated from each LOS combination (and then modified reducing increasing a certain %). I mean, I decided in advance a fixed cost of ...
by jbas
23 Sep 2024, 16:00
Forum: Model estimation
Topic: Signs of coefficients are complete opposite
Replies: 9
Views: 111720

Signs of coefficients are complete opposite

Hello there,

I recently ran this SCE to collect information on individuals’ willingness to purchase MaaS bundles. Basically, each bundle includes free minutes of biclycle, electric scooter, taxi… at a price. And there are three bundles that offer more and more free minutes at a higher price. Prices ...
by jbas
14 Jun 2021, 16:23
Forum: Models and estimation
Topic: Elasticities in MNL
Replies: 5
Views: 26644

Re: Elasticities in MNL

Hi, thanks for your reply.

It was precisely reading Train's that I wondered if my results were wrong. But I didn't clearly understood it.

Thanks a lot for the clarification.

J.
by jbas
09 Jun 2021, 10:24
Forum: Models and estimation
Topic: Elasticities in MNL
Replies: 5
Views: 26644

Elasticities in MNL

Hi all,

I came up with a doubt taking a look at the calculation of elasticities in a multinomial logit. Shouldn't the elasticities and cross-elasticities sum up to 1 due to the IIA property? It can be seen in Apollo_example_3.r that this is not the case. And it is certainly not in my models either ...
by jbas
24 Feb 2021, 17:19
Forum: Bug reports
Topic: Estimates not appearing
Replies: 4
Views: 27829

Re: Estimates not appearing

Sure, will do.
by jbas
19 Feb 2021, 15:51
Forum: Bug reports
Topic: Estimates not appearing
Replies: 4
Views: 27829

Re: Estimates not appearing

Thanks for your reply.
Sure, here it is.


```{r Init, include=FALSE}
print("To strive, to seek, to find, and not to yield.")
```


```{r Libraries, include=FALSE}
suppressWarnings(suppressMessages(library(apollo)))
suppressWarnings(suppressMessages(library(dplyr)))
```


```{r, include=FALSE ...
by jbas
18 Feb 2021, 12:58
Forum: Model specification
Topic: Cross-nested specification
Replies: 1
Views: 20114

Cross-nested specification

Hi,

I'm finding trouble in estimating a CNL specification that is slighlty different than that shown in the examples.
In Apollo_example_6.r, as the manual explains, there are three nests; One for air and rail, One of Bus and Rail, and one in which Car is all alone. Since car is on its own, the ...

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