北京大学：《中级微观经济学》课程教学资源（PPT课件讲稿，英文版）Chapter Nine Buying and Selling

Budget Constraints revisited x2 p1X1+p2X2=p1o1+p202 Budget set {(x1,x2)P1x1+P2X2sP11+p202, x1≥0,X2≥0

Budget Constraints Revisited x2 1 x1 2 p1 x1 + p2 x2 = p11 + p22 Budget set   ( , ) , , x x p x p x p p x x 1 2 1 1 2 2 1 1 2 2 1 0 2 0 +  +    

Budget Constraints revisited x2 Changing the endowment 15002

Budget Constraints Revisited x2 x1 (1 ’,2 ’) (1 ”,2 ”) (1 ,2 ) Changing the endowment

Budget Constraints revisited x2 p1X1+p2X2=p1o1+p202 Changing prices of the endowment p1x1+p2X2=p101+p202

Budget Constraints Revisited x2 1 x1 2 p1 x1 + p2 x2 = p11 + p22 p1 x1 p2 x2 p1 1 p2 2 ' ' ' ' + =  +  Changing prices of the endowment

Budget Constraints revisited x2 p1X1+p2X2=p1o1+p202 Budget set p1x1+p2x2=p1a1+p202

Budget Constraints Revisited x2 1 x1 2 p1 x1 + p2 x2 = p11 + p22 p1 x1 p2 x2 p1 1 p2 2 ' ' ' ' + =  +  Budget set

Budget Constraints revisited The endowment point is always on x2 the budget constraint p1X1+p2X2=p1o1+p202 p1x1+p2X2=p101+p202

Budget Constraints Revisited x2 1 x1 2 p1 x1 + p2 x2 = p11 + p22 The endowment point is always on the budget constraint. p1 x1 p2 x2 p1 1 p2 2 ' ' ' ' + =  + 