▁is ▁now ▁known ▁as ▁the ▁c ob web ▁model . ▁ ▁A ▁more ▁formal ▁deriv ation ▁of ▁this ▁model ▁was ▁made ▁later ▁by ▁Nicholas ▁K ald or , ▁who ▁is ▁largely ▁cred ited ▁for ▁its ▁ex position . ▁ ▁Application ▁ ▁Much ▁of ▁classical ▁econom ics ▁can ▁be ▁presented ▁in ▁simple ▁geometric ▁terms ▁or ▁elementary ▁mathematical ▁notation . ▁Mathemat ical ▁econom ics , ▁however , ▁convention ally ▁makes ▁use ▁of ▁calculus ▁and ▁matrix ▁algebra ▁in ▁economic ▁analysis ▁in ▁order ▁to ▁make ▁powerful ▁claims ▁that ▁would ▁be ▁more ▁difficult ▁without ▁such ▁mathematical ▁tools . ▁These ▁tools ▁are ▁pr ere quis ites ▁for ▁formal ▁study , ▁not ▁only ▁in ▁mathematical ▁econom ics ▁but ▁in ▁contemporary ▁economic ▁theory ▁in ▁general . ▁Econom ic ▁problems ▁often ▁involve ▁so ▁many ▁variables ▁that ▁mathematics ▁is ▁the ▁only ▁practical ▁way ▁of ▁attack ing ▁and ▁solving ▁them . ▁ ▁Alfred ▁Marshall ▁argued ▁that ▁every ▁economic ▁problem ▁which ▁can ▁be ▁quant ified , ▁analyt ically ▁expressed ▁and ▁solved , ▁should ▁be ▁treated ▁by ▁means ▁of ▁mathematical ▁work . ▁ ▁Econom ics ▁has ▁become ▁increasing ly ▁dependent ▁upon ▁mathematical ▁methods ▁and ▁the ▁mathematical ▁tools ▁it ▁emp lo ys ▁have ▁become ▁more ▁s oph istic ated . ▁ ▁As ▁a ▁result , ▁mathematics ▁has ▁become ▁consider ably ▁more ▁important ▁to ▁profession als ▁in ▁econom ics ▁and ▁fin ance . ▁Gr adu ate ▁programs ▁in ▁both ▁econom ics ▁and ▁fin ance ▁require ▁strong ▁under grad uate ▁prepar ation ▁in ▁mathematics ▁for ▁ad mission ▁and , ▁for ▁this ▁reason , ▁attract ▁an ▁increasing ly ▁high ▁number