Economists discount any factors that would not influence the thinking of a rational person. These things are supposedly irrelevant. But unfortunately for the theory, many supposedly irrelevant factors do matter.

Economists create this problem with their insistence on studying mythical creatures often known as Homo economicus. I prefer to call them “Econs”— highly intelligent beings that are capable of making the most complex of calculations but are totally lacking in emotions. Think of Mr. Spock in “Star Trek.” In a world of Econs, many things would in fact be irrelevant.

No Econ would buy a larger portion of whatever will be served for dinner on Tuesday because he happens to be hungry when shopping on Sunday. Your hunger on Sunday should be irrelevant in choosing the size of your meal for Tuesday. An Econ would not finish that huge meal on Tuesday, even though he is no longer hungry, just because he had paid for it. To an Econ, the price paid for an item in the past is not relevant in making the decision about how much of it to eat now.

According to recent surveys, between 20 and 25 percent of their permanent residents are middle class; roughly 60 percent are solidly working class or working poor who labor incredibly hard, advocate fundamental American values and aspire to the American dream for their children. Their youth share their parents’ values, expend considerable social energy avoiding the violence around them and consume far fewer drugs than their white working- and middle-class counterparts, despite their disproportionate arrest and incarceration rates.

In all inner-city neighborhoods, however, there is a problem minority that varies between about 12.1 percent (in San Diego, for example) and 28 percent (in Phoenix) that comes largely from the disconnected youth between ages 16 and 24.