In the odd case of Page, we know that his mother came from a Zionist household and had moved to Israel, but the background of his father, the late computer-science professor Carl Victor Page, is obscure. A Google search reveals only that his paternal grandfather had been an autoworker and labor activist, and that his father despised religion.

The Page family seemed to have cherished an old-fashioned socialist belief that in the future, ancestry would no longer matter. Ironically, the wife of Page’s partner Brin, Anne Wojcicki, cofounded that quintessential 21st-century company 23andMe, which offers DNA testing for genealogy enthusiasts.

The true problem with Forbes Israel‘s list is neither ideological nor ethical. Instead, it’s a slapdash affair with poor quality control. Forbes Israel palpably undercounts the number of American Jews on the Forbes 400 list of the richest Americans. (In 2012, it took a minimum net worth of $1.1 billion to make the 400, so everyone on the Forbes 400 is a billionaire, but a few hard-up billionaires with only $1.0 billion didn’t make the Forbes 400.)

The highest quality analysis of the Forbes 400 list by ethnicity is the one updated periodically by human-sciences blogger n/a at his race/history/evolution notes website.

To check which of the competing lists is more accurate, I’ve searched the first 21 names on which n/a and Forbes Israel disagree.

In one case, Forbes Israel categorizes as Jewish a man who appears to be a WASP, cable TV sultan Amos Barr Hostetter Jr., while n/a rightly classifies him as Northwestern European.

The other 20 disagreements consist of Forbes billionaires left off the Forbes Israel list that n/a denotes as Jewish.

I rapidly found that for 16 of those 20, n/a has a slam-dunk case based on readily accessible online evidence. For example, the Wikipedia article on former American Enterprise Institute chairman Bruce Kovner ($4.3 billion) states: “Kovner was born into a Russian Jewish family….”

Two of the disputed 20, Orange County real-estate baron Donald Bren and Indianapolis Colts owner James Irsay, are the product of mixed marriages.

That leaves only two of n/a‘s 20 whom I couldn’t easily document: banker Bernard Saul II and Miami TV station owner Edmund Ansin. The first has a stereotypical Jewish name, while the second is a relatively rare name that has left me stumped. Ansin’s father is said to be an immigrant from Ukraine who opened a shoe factory in Worcester, MA.

In general, I found that n/a‘s accuracy is better by far.

Overall, n/a states that 140 of the Forbes 400 rankings of richest Americans, or 35 percent, are Jewish.

Perhaps that 35 percent figure is slightly overstated by fully counting individuals of mixed backgrounds, such as Microsoft CEO Steve Ballmer. Then again, n/a may be missing a roughly similar number of non-Jewish names of billionaires who are a half or a quarter Jewish in their mother’s lines, so it may all balance out.

In general, however, the question of how to count people of partial Jewish ancestry is, no matter how fascinating in theory, still difficult at present. The current denizens of the Forbes 400 (average age 66) largely come from generations when mixed marriages were fairly rare, so solving this methodological issue can reasonably be deferred for a few more years.

Jews are usually said to make up about two percent of the US population and perhaps three percent of the older generation that dominates the Forbes 400. Therefore, Jews are roughly 17 times more likely per capita to make the Forbes 400 than is the rest of the American population.

This 35 percent Jewish figure has been fairly stable since n/a started his analyses in 2009. The first careful analysis of the Forbes 400 was performed by Nathaniel Weyl back in 1987, when he found 23 percent were Jewish. That suggests a sizable increase in Jewish representation among plutocrats over the last generation. Yet bear in mind that’s only one data point from the past. I’ve been casually following the Forbes 400 for 30 years, and membership shifts frequently due to various bubbles.

n/a has also done a quick and dirty look at Forbes‘s global list of 1,426 billionaires (#1, by the way, is Lebanese-Mexican Carlos Slim). Unlike Forbes Israel‘s estimate of 11 percent Jewish, n/a comes up with over 17 percent. Note that this is pretty much of a SWAG for Eastern Europe, where it’s harder for an Anglophone to look up biographical information. Still, this estimate would mean that per capita, Jews are a little over 100 times more likely to become billionaires than the rest of the human race.

In summary, as an Israeli might tell you, an informed opinion is better than an uninformed one.