WORTH THE DEFENDING:

A new paper by Shawn Grover, a policy analyst at Canada's Department of Finance, and John Helliwell, professor emeritus at the University of British Columbia, finds that married people are generally happier than unmarried people.

It's a well-researched area and typically opens up debate over whether the effect is one of correlation or causation-are generally happier people simply more likely to get married in the first place?

Messrs. Grover and Helliwell delve into data from three separate surveys and conclude married individuals are "more satisfied, suggesting a causal effect, even after full allowance is made for selection effects."

The benefits may be greatest immediately after marriage but aren't fleeting and appear to have the most important impact in middle age. And the effect is especially strong for close couples.

"The well-being benefits of marriage are on average about twice as large for those...whose spouse is also their best friend," the study adds.

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