Maybe those economists would be willing to explain why a FEDERAL minimum wage should be enacted, when the cost of living varies so greatly from state to state?
$10.10/hour, which is what they are calling for, is roughly $20,000/year. A person living in New York City would need $44,000/year to enjoy the same standard of living as someone making $20,000 in Atlanta. For Seattle, it would be close to $25,000. Same with Central New Jersey. In Joplin, MO, your money would go further - you'd need only $18,000.
http://money.cnn.com/calculator/pf/cost-of-living/
How do these economists justify a national minimum wage when they, of all people, should know that there is no "National Cost Of Living"?
Given that fairly obvious hole in this argument, it's not really any wonder that only 600 of the over 12,000 economists in this country would be willing to sign onto such a ridiculous notion.
https://www.aeaweb.org/
Economists to not unilaterally agree on everything. 600 is a pretty small sample - and in scanning the list of signers it should be noted that most of them are university professors. That group tends to lean to the left in a great majority - so really your question should read, "600 Liberals, who happen to be economists or economics professors, signed a letter ..."
That is no surprise at all, and means nothing.
Although seven Nobel Laureates recently, endorsed an increase in the minimum wage, all they could say was that it wouldn't hurt, and might have a slight stimulating effect on the economy. Others, including last year's three winners, would not make such an endorsement. Eugene Fama, one of the three, wrote a letter saying,
"“I am against the concept of a mandated minimum wage,” Fama said in an e-mail. “Wages should be determined in the open market, without government interference.”
Milton Friedman, one of the most notable Nobel Prizewinners who has studied the minimum wage for over 50 years is against an increase as well ..
https://www.youtube.com/watch?v=ca8Z__o52sk