Hi Stephane,
Thank you so much for the clarification. I really appreciate your help!
Best,
Ariana
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Search found 10 matches
- 02 Feb 2022, 02:36
- Forum: Models and estimation
- Topic: including socioeconomic variables in the utility functions
- Replies: 2
- Views: 5066
- 31 Jan 2022, 04:00
- Forum: Models and estimation
- Topic: including socioeconomic variables in the utility functions
- Replies: 2
- Views: 5066
including socioeconomic variables in the utility functions
Hello, In my dataset, I have many socioeconomic variables such as age_group, Disability, Income_group. I have 4 mode choices including Drive, Ride, Bus, Walk. When I put all the socioeconomic variables in each of the utility functions, it leads to over-specification of variables. What is the solutio...
- 17 Dec 2021, 17:32
- Forum: Estimation results
- Topic: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
- Replies: 11
- Views: 8543
Re: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
Stephane,
I got it! Thanks a lot for your help!
I got it! Thanks a lot for your help!
- 09 Dec 2021, 16:54
- Forum: Models and estimation
- Topic: defining a base category
- Replies: 1
- Views: 4921
defining a base category
Hello, I have a basic question about defining utility functions in Apollo. When we want to fit a multinomial logit regression, should we consider one of the alternatives as a base category like this? V[["A"]]= b_cov*cov_A + b_acc1*acc1_A + b_acc2*acc2_A + b_bid * bid_A V[["B"]]= ...
- 09 Dec 2021, 15:53
- Forum: Estimation results
- Topic: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
- Replies: 11
- Views: 8543
Re: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
Stephane,
Sorry for my late response. Yes. I also tried that and still the bus cost coefficient has a positive sign.
Sorry for my late response. Yes. I also tried that and still the bus cost coefficient has a positive sign.
- 03 Dec 2021, 01:02
- Forum: Estimation results
- Topic: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
- Replies: 11
- Views: 8543
Re: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
Thanks, yes, here is the results: Estimates: Estimate s.e. t.rat.(0) Rob.s.e. Rob.t.rat.(0) A_drive_time -0.27983 0.11261 -2.4850 0.09830 -2.8468 B_ride_time -0.19440 0.10766 -1.8057 0.09960 -1.9518 A_Car 0.18109 0.80249 0.2257 0.77829 0.2327 A_driving_Freq 2.10043 0.46973 4.4716 0.46995 4.4695 C_wa...
- 02 Dec 2021, 16:51
- Forum: Estimation results
- Topic: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
- Replies: 11
- Views: 8543
Re: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
Hi Stephane,
Thanks. I have attached the table as an image file:
Best,
Ariana
Thanks. I have attached the table as an image file:
Best,
Ariana
- 29 Nov 2021, 15:29
- Forum: Estimation results
- Topic: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
- Replies: 11
- Views: 8543
Re: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
Hi Stephane, Here is the pivot table of the bus_cost column: Row Labels Count of bus_cost 0 21 1 23 1.1 103 1.5 3 2.2 1 3.35 1 4.5 1 (blank) Grand Total 153 For 21 people, the price is zero, because the bus option is not available for them. Thanks! Ariana
- 29 Nov 2021, 02:37
- Forum: Estimation results
- Topic: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
- Replies: 11
- Views: 8543
Re: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
Hi Stephane, Thank you so much for your helpful answer! Regarding the second one, 20 out of 153 individuals chose bus as their mode choice. While bus_time varied among these individuals, the price for all the 20 individuals was the same. Is this the reason that I get this unexpected sign? Best, Ariana
- 28 Nov 2021, 02:54
- Forum: Estimation results
- Topic: In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
- Replies: 11
- Views: 8543
In multinomial logit regression; NaNs produced, an unexpected sign of one of the coefficients
Hello, I wanted to do a multinomial logit model for travel mode choice on my dataset. 1- When I want to estimate alternate specific constants, the results are strange and the errors are too big. 2-Also, the sign of the beta parameter for the "bus_cost" variable is positive. But a positive ...