Speaking strictly from publishing an Academic Paper, if your data can not be released, peer reviewed, and the same conclusions be reached by peer review. Then it’s just GIGO (Garbage In, Garbage Out).
That’s why I have stated on here numerous times, use Google Scholar, then go to the footnotes. See if the citations are reliable.
If not it’s no better than an article from “The Onion” or “The Babylon Bee”
It doesn’t surprise me at all, that he won’t release his data, how he collected it, what languages he used or what the parameters of his search was/is. Just another liberal Professor under the pressure of publish or die, so prevalent in so many universities.
Why I have done studies on mass shootings over the past 100 years in 187 languages. The planet Klaatu averages 700 mass shootings a day. Sorry, I can’t tell you where the planet Klaatu is, nor can I tell you what languages I used, but I traveled to all 187 of those countries and spent years going through their archives with me and my crack team of researchers
What I just printed in the last paragraph has as much academic weight as that Professor from UA did.
If a study/research paper won’t cite source material & study parameters (which are the work’s backbone), it’s not worth the paper it’s written on to me. I’ll find a more trustworthy source for my info…
At the rate Toilet Paper has been bought up in the Covid 19 crisis, it does have some value at least, I can have something to line the bottom of the bird cage withor if needed to wipe other areas with. 
