| The popular press has triumphantly announced that the cause of the obesity epidemic is “junk food.” After a moment’s reflection, however, it seems likely that the true causal structure of the obesity epidemic can be neither single-equation nor univariate. Therefore, while the hypothesis that “junk food” is the cause of obesity has little a priori plausibility, these articles in the popular press present a testable hypothesis that, in spite of some measurement impossibilities, is tested here. While one can always argue about p values etc., it is safe to say that the results show no evidence to indicate support for a causal link. The second section of the paper explains this result and suggests a rudimentary structural model of obesity that begins to address... |