number of Indicator of latent variable (Reflective model)

[Capcap1668]

Dear everybody,

I am a new user for Smartpls 4. while I am doing some initial analysis, I have a question in my mind. What are the minimum number of indicators for a latent variable? Are there any requirements or procedures for number of indicators of a latent variable?

Thank you for your support,

I wish you a good working week,

Hung

[jmbecker]

The minimum number is 1. This would be a single indicator constructs, which means that the construct will equal the indicator.

In general, you often read that you need 3 to 4 (reflective) indicators, but this is not a technical requirement for PLS. It is more a recommendation in terms of psychometric properties. Multiple indicator measurement has the advantage that you will capture the concept from several slightly different angles to better tap into the core concept and to parcel out measurement error. In fact, the more indicators the better from a psychometric standpoint. But then there are also other considerations in terms of questionnaire fatigue that make long scales not always better in practice, because respondents might not answer them so carefully.
If you have formative / composite indicators, you will need to be able to argue that you capture the whole construct domain. That might require 2 indicators on the one context and and 8 indicators for another concept.

[Capcap1668]

Thank you for your quick response. I can be more clear on the number of latent variables. In addition, it would be better if you could give me some papers or documents as a base for the minimum number of indicators (or for what you have denote). Thank you