I wish they gave a source for the relationship between using these pronouns and telling the truth.
Also, just looking at facebook users introduces a bloody selection bias.
I wish they gave a source for the relationship between using these pronouns and telling the truth.
Here's what the paper says:
"The honesty of the status updates written by the participants was assessed
following the approach introduced by Newman, Pennebaker, Berry, and Richards
(2003) using LIWC. Their analyses showed that liars use fewer first-person
pronouns (e.g., I, me), fewer third-person pronouns (e.g., she, their), fewer
exclusive words (e.g., but, exclude), more motion verbs (e.g., arrive, go),
and more negative words (e.g., worried, fearful; Newman, Pennebaker, Berry, &
Richards, 2003)."
Their sample pool covers better than 25% of the human population.
If nothing else, it's worth considering the demographics: within the USA, women use Facebook at a higher rate than men; people with some college education use Facebook at a higher rate than either college graduates or adults who've never been to college; Facebook use rate is roughly negatively correlated with income level; use of Facebook is negatively correlated with age (http://www.pewinternet.org/2016/11/11/social-media-update-20...). So the leftover US population skews male and slightly higher-income than the Facebook population. And globally, Facebook use is correlated with national wealth (minus some outliers). So there's clearly a sampling bias, and that's worth understanding.
That said, whether the results would be any different is hard (impossible?) to say without actually trying a different sampling methodology, and I suspect the results from this study are valid, sampling bias notwithstanding.