, ▁for ▁example , ▁that ▁going ▁to ▁college ▁can ▁function ▁as ▁a ▁cred ible ▁signal ▁of ▁an ▁ability ▁to ▁learn . ▁ ▁Assuming ▁that ▁people ▁who ▁are ▁sk illed ▁in ▁learning ▁can ▁finish ▁college ▁more ▁easily ▁than ▁people ▁who ▁are ▁un sk illed , ▁then ▁by ▁finishing ▁college ▁the ▁sk illed ▁people ▁signal ▁their ▁skill ▁to ▁pros pective ▁employ ers . ▁ ▁No ▁matter ▁how ▁much ▁or ▁how ▁little ▁they ▁may ▁have ▁learned ▁in ▁college ▁or ▁what ▁they ▁studied , ▁finishing ▁functions ▁as ▁a ▁signal ▁of ▁their ▁capacity ▁for ▁learning . ▁ ▁However , ▁finishing ▁college ▁may ▁merely ▁function ▁as ▁a ▁signal ▁of ▁their ▁ability ▁to ▁pay ▁for ▁college , ▁it ▁may ▁signal ▁the ▁willing ness ▁of ▁individuals ▁to ▁ad here ▁to ▁orth odox ▁views , ▁or ▁it ▁may ▁signal ▁a ▁willing ness ▁to ▁comp ly ▁with ▁authority . ▁ ▁Screen ing ▁Joseph ▁E . ▁St ig l itz ▁pione ered ▁the ▁theory ▁of ▁screen ing . ▁In ▁this ▁way ▁the ▁under in formed ▁party ▁can ▁indu ce ▁the ▁other ▁party ▁to ▁reve al ▁their ▁information . ▁They ▁can ▁provide ▁a ▁menu ▁of ▁choices ▁in ▁such ▁a ▁way ▁that ▁the ▁choice ▁depends ▁on ▁the ▁private ▁information ▁of ▁the ▁other ▁party . ▁ ▁Ex amples ▁of ▁situations ▁where ▁the ▁s eller ▁usually ▁has ▁better ▁information ▁than ▁the ▁bu yer ▁are ▁numerous ▁but ▁include ▁used - car ▁sales people , ▁mort g age ▁bro k ers ▁and ▁loan ▁origin ators , ▁stock bro k ers ▁and ▁real ▁estate ▁agents . ▁ ▁Ex amples ▁of ▁situations