That's really interesting; the research methodology seems perhaps a bit flawed though. They didn't seem to explain the "power" metric very well when asking the question (in section 3.1 they said the question was ranked on a scale of 1 to 7 from powerless/lacking control to powerful/in control which seems a bit abstract). The ratio of men to women was 3:7 and in both annual income and age the ranges were quite small focusing mainly on an average age of 30 +- 5 years and annual income between $40k-$60k.