The “problem like this” I was referring to was “health advice and information is often faulty,” not “linear regression analysis of mortality effects from supplementation is faulty.”
I’d like to get better at correcting for the former while avoiding the (potentially enormous) amount of learning and effort involved in getting better at all necessary forms of the latter.
From what I can tell, you’re saying “there is no way; the two are inextricably linked.” In which case, I guess I’ll just wait until they get better at it.
All of those points are true, but there’s one I’d like to flag as true but potentially misleading:
Linear regression assumes a linear relationship
Linear regression does assume this in that it tries to find the optimal linear combination of predictors to represent a dependent variable. However, there’s nothing stopping a researcher from feeding in e.g. x and x squared as predictors, and thereby finding the best quadratic relationship between x and some dependent variable.
The “problem like this” I was referring to was “health advice and information is often faulty,” not “linear regression analysis of mortality effects from supplementation is faulty.”
I’d like to get better at correcting for the former while avoiding the (potentially enormous) amount of learning and effort involved in getting better at all necessary forms of the latter.
From what I can tell, you’re saying “there is no way; the two are inextricably linked.” In which case, I guess I’ll just wait until they get better at it.
The general advice here is
Not all regression is the same; beware anyone who reports doing “a regression”
Linear regression assumes a linear relationship
Don’t trust a report that bases its authority on numbers if you can’t say what those numbers mean
A conclusion can be both true and misleading
A little unreflective folk-psychology (“vitamins” as being “more is better” instead of having a dose-response curve) can do a lot of damage
All of those points are true, but there’s one I’d like to flag as true but potentially misleading:
Linear regression does assume this in that it tries to find the optimal linear combination of predictors to represent a dependent variable. However, there’s nothing stopping a researcher from feeding in e.g. x and x squared as predictors, and thereby finding the best quadratic relationship between x and some dependent variable.