On Sun, 28 Aug 2016 20:24:04 -0700, Mike Palij wrote:
Although I have been somewhat following the "replication crisis" I did not know the "sad face" result and its apparent importance. Failure to replicate this result is the focus of this article in Slate; see: http://www.slate.com/articles/health_and_science/cover_story/2016/08/can_smiling_make_you_happier_maybe_maybe_not_we_have_no_idea.html
In looking over the Slate article above, it occurred to me that the author and some of the researchers he quotes misses some important points, namely:
(1) Psychologists do experimental research in order to establish causal relationships between/among variables. What make scientific research valuable is that these causal relationships should hold up either in all conditions (i.e., a main effect; such as gravity operates the same throughout the universe) or interacts with other variables such that the causal relationship changes in magnitude or even presence (i.e., disappears; antibiotic treatment of tuberculosis is more effective with inpaitent groups who receive the treatment on a regular schedule as well as other supports as compared to a homeless person with HIV/AIDS who has to self-administer meds). The establishment of a causal relationship is a critically important part of our valid knowledge of reality. (2) Issues regarding whether or not a causal relationship exists fall under the heading of internal validity and one does not have to read Campbell & Stanley every night before going to sleep (or does one?) to be reminded of the threats to internal validity as well as factors that can give rise to spuriously significant result (i.e., Type I errors, experimenter effects and other reactive effects). The Slate article does not mention the importance of establishing causal effects in experiments, the degree of internal validity, and the threats to internal validity (to be fair, there are a few comments that can be interpreted as threats to internal validity but these are presented without the validity context). (3) The extent to which a causal relationship exists beyond the original situation (i.e., the experimental situation) is an issue concerning external validity and ecological validity. Treatment of tuberculosis is an example of both: (a) some antibiotics may or may not work with certain strains of TB, and (b) the schedule of everyday treatment should follow as closely as possible the schedule used in the experimental study -- something that is reasonable in an inpatient treatment facility or with people with stable living conditions with good social supports but unreasonable for homeless people with other serious illness. I raise this point because at the end of the article Strack, defender of the "sad face" effect, comments on a meta-analysis that found that roughly half of the replication found the effect and half did not, overall no causal relationship. But the article says the following: |So when Strack looks at the recent data he sees not a |total failure but a set of mixed results. Nine labs found the |pen-in-mouth effect going in the right direction. Eight labs |found the opposite. So, toss a coin and you'll get the profanity of getting a statistically significant or nonsignificant result (or, for people with NHSTphobia, an effect size greater than zero or an effect size equal to zero or less than zero). ||Instead of averaging these together to get a zero effect, |why not try to figure out how the two groups might have |differed? Maybe there's a reason why half the labs could |not elicit the effect. Maybe, but the most parsimonious explanation is that there is no effect. Strack appears to be making an argument based on the limited generality of the causal relationship, that it interacts with other variables, and this is why it is present in some research but absent in others. But this is a post hoc explanation and the Slate article does not identify which variables might be operating to either suppress the causal effect or to allow it to be expressed (to be fair, I have not read Strack's original article on this point and I do not know if he has shown that re-analyses of data from these studies show which variables suppress/express the effect, then he may be on solid ground though one might argue that he is on a fishing expedition in such analyses -- if certain 3rd variables keep showing up, then one has to do the experiment that has conditions with that/those 3rd variables present and absent, and showing that the effect depends upon the presence/absence of these variables, otherwise he's just blowing smoke). Again, I am reminded of the DiCara situation and Miller & Dworkin's inability to replicate DiCara's original finding of conditioning of the autonomic nervous system: M&D still believe the effect was real even though they were not able to replicate it -- nor has anyone else since the publication of their results. Perhaps researchers need to be reminded of the tentativeness of our knowledge and better appreciate which causal relationships can be reliably shown and which cannot. -Mike Palij New York University [email protected] --- You are currently subscribed to tips as: [email protected]. To unsubscribe click here: http://fsulist.frostburg.edu/u?id=13090.68da6e6e5325aa33287ff385b70df5d5&n=T&l=tips&o=49349 or send a blank email to leave-49349-13090.68da6e6e5325aa33287ff385b70df...@fsulist.frostburg.edu
