1 9 9 6 - 2 0 1 4 , ▁she ▁agre es ▁with ▁Lewis ▁that ▁it ▁would ▁not ▁have ▁been ▁possible ▁to ▁provide ▁accurate ▁predictions ▁re lying ▁sole ly ▁on ▁economic ▁models ▁and ▁without ▁consult ing ▁policy , ▁financial ▁and ▁business ▁exper ts . ▁ ▁While ▁comple ting ▁her ▁Ph . D . ▁in ▁Econom ics , ▁Hugh es - C rom wick ▁conducted ▁research ▁concerning ▁household ▁energy ▁use ▁in ▁N airo bi , ▁Ken ya . ▁She ▁explo ited ▁a ▁household ▁survey ▁conducted ▁by ▁the ▁Ken yan ▁government ▁which ▁asked ▁households ▁to ▁specify ▁the ▁type ▁of ▁energy ▁they ▁used ▁for ▁he ating . ▁The ▁goal ▁of ▁the ▁paper ▁was ▁to ▁explain ▁changes ▁in ▁fuel ▁demand ▁as ▁a ▁result ▁of ▁the ▁price ▁increase ▁in ▁pet role um ▁in ▁the ▁ 1 9 7 0 s . ▁By ▁looking ▁at ▁the ▁effect ▁of ▁income ▁changes ▁on ▁fuel ▁demand , ▁Hugh es - C rom wick ▁found ▁that ▁electric ity ▁consumption ▁was ▁income ▁el astic , ▁gas ▁consumption ▁was ▁income ▁in el astic , ▁and ▁char co al ▁consumption ▁dep ended ▁on ▁char co al ▁app liance ▁ownership ▁and ▁number ▁of ▁household ▁members . ▁ ▁Media ▁appearances ▁ ▁Hugh es - C rom wick , ▁as ▁a ▁Senior ▁Econom ist ▁with ▁the ▁University ▁of ▁Michigan ▁Energy ▁Institute , ▁regularly ▁att ends ▁the ▁Transport ation , ▁Econom ics , ▁Energy ▁and ▁Environment ▁conference ▁hosted ▁by ▁the ▁inst itute . ▁At ▁the ▁ 2 0 1 8 ▁conference , ▁she ▁was ▁a ▁present er ▁on ▁a