Undermutualagreements,economictheoryimpliesthatthetotalamountoftenantinputscontractedwillbetheamountwhichyieldsthehighest（q-f）/h,,thehighestvalueof（q-f）//hasaresultofincreasingthestipulatedamountoftenantinput,thereisassociatedanupwardshiftofq/www.youxs.org（www.youxs.org）；thelatterrepresentsthemarginalproductivityofadditionaltenant（www.youxs.org）input,whichincreasesatadecreasingrate（www.youxs.org）.[3]Thehighest（q-f）/h-associatedwithaspecificf/hcurve-isobtainedwhenthemarginalupwardshiftsoff/handq/hareequal,o,whichdefinesf/h,,thecropschosentobeplantedorrotated,andthemethodofproduc-ingthem,are,bydefinition,thosewhichyieldthehighestpresentvalueoflandtothelandowner,thatis,whichmaximizerentalannuity.[4]Therelevantvalueof（q-f）/h,oraveragerent,fordecisionmakingisthusthehighestonederivedfromalternativepairsofq/handf/www.youxs.org（q-f）/hdefinesthecostoflandperacreasafactorofproduction.[5]

Themarginalproductofland,

—or

infigure2—cutsq/hand（q-f）/,T1,iswhere（q-f）/（T1）,theequilibriumrentalpercentageequals（q-f）/hdividedbyq/h（atT下标内容）.Thatis,therentalpercentage,r,equalsar/,say70percent,weplotthemarginalcontractrentcurve,

r,asthispercentageof

ateverypoint.

Sincethetenantcontractstopayapercentageofthetotalproduct,asindicatedby

r,thecostoflandis,thetenantpreferstoemploylandtothepointwhere

iszero（whileholdinghisfarminginputsconstantascontractuallystipulated）.Thelandowner,ontheotherhand,willlimitthetenantsholdingtoT1,andparceltheremainderofhistotalholdingtoothertenantsundersimilarcontractualarrangements.[6]ThelandownercannotsuccessfullyrestrictlandsizetolessthanT1,sincewithrentalpercentagerthetenantsalternativeearningwillbehigherelsewhereandhewillgiveupthetenancy.

,”specific”factorsofproduction,forexample,,themoreproductivetenantswillbetheintramarginaltenants,andthef/ngefficiencieseveniftherearenocostsassociatedwithdiscrimination,becauseland-lordsemployingmarginaltenants（leastproductivetenants）willbidthemoreproductivetenantsawayfromadiscriminatinglandlord.

Second,eveniflandishomogeneous,erentalvalueperunit-thatis,the（q-f）/hcurvesindifferenttenantfarmsyieldequalheightsattheirpeaks-thelandsizesfordifferenttenantswilldifferiftheproductionfunctionsofthesetenantsdiffer.[7]Thisalsoimpli,inmaximizingtherentalannuityofhislandholdings,theownerwillassigndifferentlandsizesandchargedifferentrentalpercentagestodifferenttenantsifth,givenhomogeneouslands,themarginalproductivityoflandforeachfarmmustbeequalateverymargin,foritisatthehighestvalueof（q-f）/hthatlandsizesaredivided.

Third,thefarmingcost（otherthanthecostofland）,thef//handf/hasinfigure3,thef/hminusthelandownersinputcostwillbelower,thusdefiningahigher（q-df）*/（q-f）*/hcurve（notdrawn）measuresnotonlythecostofland（rent）,butalsothelandownersnonlandfarmingcost.[8]Therentalpercentagechargedbythelandownerwillaccordinglybehigher,withanupwardshiftof

:itdoesnotmatterwhetherthelandownerrequiredthetenanttoinvestmoreinlandandchargesalowerrentalpercentageorwhetherthelandownerinvestsinlandhimselfandchargesthetenantahigherrentalpercentage;theinvestmentwillbemadeifitleadstoahigherrentalannuity.[9]Itfollowsthatfora,thetenantmayraisethefarminginputsbycooperatingwiththelandowner,bysubleasing,byhiringfarmhands,byborrowing,,thedifferenttenantinputrequirementsinfarmsofdifferentlandgradesandproductionfunctionswillmatchtenantswithdifferentinputendowmentsaccordingly.