code: function getScore (stats) {
      return calc.aggregate([TITLE_W, COMPETITOR_W, INSTALLS_W, RATING_W, AGE_W],
                            [stats.titleMatches.score, stats.competitors.score,
                             stats.installs.score, stats.rating.score, stats.age.score]);
    }
docs: /*
  Calculate an aggregate score according to each stat's weight.