A behind-the-scenes blog about research methods at Pew Research Center. For our latest findings, visit pewresearch.org. Many of Pew Research Center’s survey analyses show relationships between two ...

Last month we explored how to model a simple relationship between two variables, such as the dependence of weight on height 1. In the more realistic scenario of dependence on several variables, we can ...

If the continuous function u satisfies the inequality $\mathrm{u}(\mathrm{x},\mathrm{y})\le \mathrm{f}(\mathrm{x},\mathrm{y})+{\int }_{0}^{\mathrm{x}}{\int }_{0 ...

The operator convex functions of two variables are characterized in terms of a non-commutative generalization of Jensen's inequality. Journal Information This monthly journal, begun in 1950, is ...