Honestly, I haven't looked into your claim. But just off-hand, I'm very skeptical of any evidence that minimum wage increases cause anything but a decrease (even if tiny) in employment. How many goods in the world do price increases cause an increase of demand?
Economists have a term for this type of good, "Giffen Good"[1]. And for obvious reasons, they almost never exist. When does an increase lead to a demand increase? Why would employers demand more labor with a price floor than they would without one?
You should read the article I linked. : ) It's a very solid meta-analysis including pretty much every peer reviewed article on the subject of the past few decades.
> ... When does an increase lead to a demand increase? Why would employers demand more labor with a price floor than they would without one?
The article explicitly doesn't go into why, but I can think of a few reasons.
Totally off hand, I'd put my money on the fact that businesses that employ minimum wage earners tend to also be disproportionately patroned by minimum wage earners. Add to that the fact that minimum wage earners tend to pretty much immediately spend their paychecks, you're left with businesses having their customer base with more disposable income.
Why don't employers simply raise wages themselves? Aside from the implicit information asymmetry sort of denoted by this very conversation, it doesn't make sense from a sort of game theory point of view for an individual business to go out on a limb without their competitors doing the same at the same time. In my mind, that makes it a perfect opportunity for government to step in, and add some lower bounds of acceptability. This way both employees and employers can have more success.
Economists have a term for this type of good, "Giffen Good"[1]. And for obvious reasons, they almost never exist. When does an increase lead to a demand increase? Why would employers demand more labor with a price floor than they would without one?
[1] http://lexicon.ft.com/Term?term=Giffen-good