KURVA INDIFFERENCE II

Review Pertemuan Sebelumnya Budget Constraint / Kendala Anggaran Preferences Indifference Curve 4 Sifat Kurva Indifference Marginal Rate of Substitution (MRS) Optimalisasi Pilihan Konsumen

Review: Budget Constraint The budget constraint shows the various combinations of goods the consumer can afford given his or her income and the prices of the two goods. The limit on the consumption “bundles” that a consumer can afford. People consume less than they desire because their spending is constrained, or limited, by their income

Review: Budget Constraint Ice Cream (cup) Coklat (Batang) Pengeluaran utk Pengeluaran Total 100 1000 50 90 900 80 200 800 150 70 300 700 60 400 600 250 500 40 350 30 20 450 10

Review: Budget Constraint Quantity of Ice Cream 500 B Consumer’s budget constraint 100 A Quantity of Coklat

Review: Budget Constraint Quantity of Ice Cream 500 B Consumer’s budget constraint 250 50 C 100 A Quantity of Coklat Copyright©2004 South-Western

Review: Preferences Secara sederhana preferences adalah apa-apa yang diinginkan konsumen. Sekumpulan (bundle) barang & jasa yang diinginkan konsumen Setiap orang memiliki preferensi yang berbeda-beda

Review: Kurva Indifference Preference atau preferensi seseorang bisa ditunjukkan dengan kurva indifference Kurva Indifference adalah kurva yg menunjukkan kumpulan/kelompok/kombinasi konsumsi dimana konsumen memiliki tingkat utilitas / kepuasan yg sama (indifference).

Review: Kurva Indifference Quantity I2 Indifference curve, I1 of Ice Cream C B D A Quantity of Coklat Copyright©2004 South-Western

Review: 4 Sifat Kurva Indifference Kurva Indifference yg lebih tinggi lebi disukai daripada yg lebih rendah. Kurva Indifference berbentuk miring dari kiri atas ke kanan bawah. Kurva Indifference tidak saling berpotongan satu sama lain. Kurva Indifference cembung terhadap titik 0 (titik origin).

Review: The Marginal Rate of Substitution (MRS) The Marginal Rate of Substitution ditunjukkan oleh slope Kurva Indifference Adalah tingkat dimana konsumen bersedia menukarkan satu barang untuk barang yg lain. Jumlah barang yg harus diberikan agar sesorang bersedia mengurangi konsumsi barang yg lain.

Review: The Marginal Rate of Substitution (MRS) Quantity I2 Indifference curve, I1 of Ice Cream C B D 1 MRS A Quantity of Coklat Copyright©2004 South-Western

Review: The Marginal Rate of Substitution (MRS) Quantity of Ice Cream Indifference curve 14 2 1 MRS = 6 8 3 A 4 6 3 7 B 1 MRS = 1 Quantity of Coklat Copyright©2004 South-Western

Review: Optimalisasi Pilihan Konsumen Combining the indifference curve and the budget constraint determines the consumer’s optimal choice. Consumer optimum occurs at the point where the highest indifference curve and the budget constraint are tangent.

Review: Optimalisasi Pilihan Konsumen Quantity I3 of Ice Cream I2 Budget constraint I1 Optimum B A Quantity of Coklat Copyright©2004 South-Western

Perubahan Keseimbangan Konsumen Perubahan Budget / Income Perubahan Harga Barang

1. Perubahan Budget / Income Perubahan Income konsumen akan menggeser budget constraint dengan arah sejajar Kenaikan income akan menggeser budget constraint ke luar / kanan Konsumen memiliki kemampuan untuk memilih kombinasi barang dan jasa pada kurva indifference yg lebih tinggi. Penurunan income akan menggeser budget constraint ke dalam / kiri Konsumen harus memilih kombinasi brg/jasa pada kurva indifference yg lebih rendah

1. Perubahan Income  Peningkatan Income Quantity of Ice Cream New budget constraint I2 1. An increase in income shifts the budget constraint outward . . . I1 New optimum 3. . . .Konsumsi Ice Cream Naik Initial optimum Initial budget constraint Quantity 2. . . . konsumsi coklat naik . . . of Coklat Copyright©2004 South-Western

1. Perubahan Budget / Income Barang Normal vs Barang Inferior If a consumer buys more of a good when his or her income rises, the good is called a normal good. If a consumer buys less of a good when his or her income rises, the good is called an inferior good.

1. Perubahan Income  Barang inferior Quantity of Bakiak New budget constraint 1. An increase in income shifts the budget constraint outward . . . I1 I2 Initial optimum 3. . . .Konsumsi Bakiak Turun New optimum Initial budget constraint Quantity 2. . . . konsumsi coklat naik . . . of Coklat Copyright©2004 South-Western

2. Perubahan Harga Barang Perubahan harga barang akan merubah kemiringan Budget Line / Garis Anggaran Turunnya harga barang akan membuat Garis Anggaran memiliki kemiringan lebih tegak Demikian juga sebaliknya

2. Perubahan Harga Barang: Harga Ice Cream Turun Quantity of Ice Cream New budget constraint 1,000 D I1 I2 New optimum 1. A fall in the price of Pepsi rotates the budget constraint outward . . . 500 B 100 A 3. . . . Konsumsi ice cream naik Initial optimum Initial budget constraint Quantity 2. . . . Konsumsi coklat turun . . . of Coklat Copyright©2004 South-Western

2. Perubahan Harga Barang A price change has two effects on consumption. Income Effect Substitution Effect

2. Perubahan Harga Barang :  Income and Substitution Effects The Income Effect Merupakan perubahan konsumsi ke dalam kurva indifference yg lebih tinggi atau lebih rendah sbg akibat perubahan harga. The Substitution Effect Merupakan perubahan konsumsi di sepanjang kurva indifference sbg akibat perubahan harga.

2. Perubahan Harga Barang :  Income and Substitution Effects Perubahan harga menyebabkan konsumsi konsumen berpindah dari satu titik ke titik dilain di sepanjang kurva indifference yg sama Ditunjukkan dari pergerakan dari titik A ke B. Income Effect Setelah berpindah dari satu titik ke titik lain, konsumen kemudian pindah ke titik di kurva indifference yg lain (lebih tinggi atau lebih rendah). Ditunjukkan dari pergerakan dari titik B ke C

2. Perubahan Harga Barang :  Income and Substitution Effects Quantity of Ice Cream I2 I1 New budget constraint C New optimum Income effect Income effect B A Initial optimum Initial budget constraint Substitution effect Substitution effect Quantity of Coklat Copyright©2004 South-Western

Menurunkan Kurva Permintaan Kurva permintaan konsumen bisa dilihat sebagai keputusan optimal seorang konsumen yg berasal dari interaksi antara budget constraint dan kurva indifference konsumen tersebut.

Menurunkan Kurva Permintaan (a) The Consumer ’ s Optimum (b) The Demand Curve for Ice Cream Quantity Price of of Ice Cream Ice Creami New budget constraint I2 Demand 750 B 250 $2 A I1 750 1 B 250 A Initial budget constraint Quantity Quantity of Coklat of Ice Cream Copyright©2004 South-Western

Giffen Goods Economists use the term Giffen good to describe a good that violates the law of demand. Giffen goods are goods for which an increase in the price raises the quantity demanded. The income effect dominates the substitution effect. They have demand curves that slope upwards.