With smaller data sets I find the summary to be less valuable than the actual paper. In this case we are talking about 4,533 twin pairs where one is a male and the other female. The female twin had a 2.8-percentage point higher probability of dropping out of high school compared to other female students, and a similar 1.9-percentage point lower probability of graduating from college. Those two numbers seems connected…
> The paper do not give out any P values [...] for their primary findings. The relative effect is large, but I interpret that more like a warning flag. Incorrect. The p-values -- all 85 of them -- are presented in the appendix[1], linked to in the first paragraph under the 'Results' heading, along with means, standard deviations, and number of observations. The article text[2] repeatedly references these tables when…
Thank you, missed the appendix. Also see that in the figure page list CI as 95%.
> These measures are already known to be strongly correlated... The paper does explicitly make clear when findings of independence are relevant
The first few paragraphs in the article here and the Significance section in the actually paper imply a strong independence. My point above is basically that the independence looks to be much weaker than a casual read might imply. It also boast with the largest study ever done on the subject, which might be true, but the absolute number are actually quite low with only a few individuals being responsible for a large effect in the data. That is one of the biggest warning signs that exist in this kind of research. I thus get skeptical, at which point I start to look why there seems to be a disconnect.