I recently became a member of the following LinkedIn groups: Consultants Network, Statistics & Analytics Consultants, and Solepreneurs.
Posted questions and responses have been relevant and useful. Other groups like Research and Methods Group for Social Sciences or Time Series in Marine Sciences exist. So, if you want forums specific to a field and/or type of analysis, you may be able to find them on LinkedIn.
Employers, when exploring candidates for a position, often check how engaged a candidate is in professionally-related social media. It appears (from my discussions with HR experts) that companies will trace each response you've made, whether your responses were "liked", and whether you're a top responder. The advice I was given was to join groups and stay moderately active.
MJ-
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Monica Johnston
Statistical Consultant & Instructor
Mostly Math
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