I would like to ask another question about ICLV model specifications: Is it appropriate to use the same socio-demographic characteristics as explanatory variables for both the latent variable and as covariates for the utility coefficients?
For example, let us assume I would like to test whether gender has an effect on the LV "environmental awareness", which in turn has an effect on the travel mode "bus" (beta coefficient "b_bus"). On the other hand, gender might have an effect on the utility of "bus", which cannot be explained by the indirect effect of the latent variable. In this case, both coefficients could be significant, i. e. the effect of gender on the LV as well as the effect of gender on the beta coefficient "b_bus". But what happens if the effect of gender is (almost) perfectly moderated by the latent variable? Can this cause identification problems? A few papers I have looked into use different socio-demographic characteristics as covariates for the utility parameters and as explanatory variables for the LV.
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ICLV model questions
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stephanehess
- Site Admin
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Re: ICLV model questions
Hi Nico
yes, and in fact, this is in my view the correct approach as it allows you to disentangle the effects. See e.g. http://www.stephanehess.me.uk/papers/jo ... A_2018.pdf
If the LV is used in both the choice part and the measurement model for indicators, but the additional parameters for the same socios are used only in the choice part, then theoretical identification is fine, but of course empirical identification might be dataset specific
Stephane
yes, and in fact, this is in my view the correct approach as it allows you to disentangle the effects. See e.g. http://www.stephanehess.me.uk/papers/jo ... A_2018.pdf
If the LV is used in both the choice part and the measurement model for indicators, but the additional parameters for the same socios are used only in the choice part, then theoretical identification is fine, but of course empirical identification might be dataset specific
Stephane
Re: ICLV model questions
Hi Stephane,
thanks for the fast reply! I saw this approach for the first time in your paper, but nowhere else. In other papers, different socio-demographic characteristics are usually used as explanatory variables for the latent variables and as covariates.
But just to get this straight: Something like this is okay and does not lead to identification problems?
thanks for the fast reply! I saw this approach for the first time in your paper, but nowhere else. In other papers, different socio-demographic characteristics are usually used as explanatory variables for the latent variables and as covariates.
But just to get this straight: Something like this is okay and does not lead to identification problems?
- b_Income_Price: direct influence of income on the price coefficient
- gamma_Income_PriceSensitivity: explanatory variable income of the latent variable "PriceSensitivity"
- lamba_PriceSensitivity_Price: influence of the LV on the price coefficient
- Indicators of the LV
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stephanehess
- Site Admin
- Posts: 1046
- Joined: 24 Apr 2020, 16:29
Re: ICLV model questions
Hi Nico
yes, this is fine. In fact, any papers that do not attempt to put the same covariates into the utility directly and into the LV are potentially misattributing the source of heterogeneity. This is the same reason why any hybrid choice model should always also incorporate random heterogeneity directly in the utility, not just through the LV
Stephane
yes, this is fine. In fact, any papers that do not attempt to put the same covariates into the utility directly and into the LV are potentially misattributing the source of heterogeneity. This is the same reason why any hybrid choice model should always also incorporate random heterogeneity directly in the utility, not just through the LV
Stephane