KURVA INDIFFERENCE II Copyright 2004 SouthWestern Review Pertemuan

KURVA INDIFFERENCE II Copyright© 2004 South-Western

Review Pertemuan Sebelumnya • • • Budget Constraint / Kendala Anggaran Prefences Indifference Curve 4 Sifat Kurva Indifference Marginal Rate of Substitution (MRS) Optimalisasi Pilihan Konsumen Copyright© 2004 South-Western

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 Copyright© 2004 South-Western

Review: Budget Constraint Ice Cream (cup) Coklat (Batang) Pengeluaran utk Total Ice Cream Coklat 0 1000 50 90 100 900 100 80 200 800 1000 150 70 300 700 1000 200 60 400 600 1000 250 50 500 1000 300 40 600 400 1000 350 30 700 300 1000 400 20 800 200 1000 450 10 900 1000 500 0 1000 Copyright© 2004 South-Western

Review: Budget Constraint Quantity of Ice Cream 500 B Consumer’s budget constraint 0 A 100 Quantity of Coklat Copyright© 2004 South-Western

Review: Budget Constraint Quantity of Ice Cream 500 250 B C Consumer’s budget constraint A 0 50 100 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 Copyright© 2004 South-Western

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). Copyright© 2004 South-Western

Review: Kurva Indifference Quantity of Ice Cream C B D I 2 A 0 Indifference curve, I 1 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). Copyright© 2004 South-Western

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. Copyright© 2004 South-Western

Review: The Marginal Rate of Substitution (MRS) Quantity of Ice Cream C B MRS D I 2 1 A 0 Indifference curve, I 1 Quantity of Coklat Copyright© 2004 South-Western

Review: The Marginal Rate of Substitution (MRS) Quantity of Ice Cream 14 MRS = 6 A 8 1 4 3 0 B MRS = 1 1 2 3 6 Indifference curve 7 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. Copyright© 2004 South-Western

Review: Optimalisasi Pilihan Konsumen Quantity of Ice Cream Optimum B A I 3 I 1 I 2 Budget constraint 0 Quantity of Coklat Copyright© 2004 South-Western

Perubahan Keseimbangan Konsumen 1. Perubahan Budget / Income 1. Perubahan Harga Barang Copyright© 2004 South-Western

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 Copyright© 2004 South-Western

1. Perubahan Income Peningkatan Income Quantity of Ice Cream New budget constraint 1. An increase in income shifts the budget constraint outward. . . New optimum 3. . Konsumsi Ice Cream Naik Initial optimum Initial budget constraint I 2 I 1 0 2. . konsumsi coklat naik. . . Quantity 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. Copyright© 2004 South-Western

1. Perubahan Income Barang inferior Quantity of Bakiak New budget constraint 1. An increase in income shifts the budget constraint outward. . . 3. . Konsumsi Bakiak Turun Initial optimum New optimum Initial budget constraint I 1 I 2 0 2. . konsumsi coklat naik. . . Quantity of Coklat Copyright© 2004 South-Western

2. Perubahan Harga Barang • Perubahan harga barang akan merubah kemiringan kurva indifference • Turunnya harga barang akan membuat kurva indifference memiliki kemiringan lebih tegak • Demikian juga sebaliknya Copyright© 2004 South-Western

2. Perubahan Harga Barang: Harga Ice Cream Turun Quantity of Ice Cream 1, 000 D New budget constraint New optimum 500 1. A fall in the price of Pepsi rotates the budget constraint outward. . . B 3. . Konsumsi ice cream naik Initial optimum Initial budget constraint 0 I 1 I 2 A 100 2. . Konsumsi coklat turun. . . Quantity of Coklat Copyright© 2004 South-Western

2. Perubahan Harga Barang • A price change has two effects on consumption. 1. Income Effect 2. Substitution Effect Copyright© 2004 South-Western

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. Copyright© 2004 South-Western

2. Perubahan Harga Barang : Income and Substitution Effects • Substitution Effect • 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 Copyright© 2004 South-Western

2. Perubahan Harga Barang : Income and Substitution Effects Quantity of Ice Cream New budget constraint C New optimum Income effect B Substitution effect Initial budget constraint Initial optimum A I 2 I 1 0 Substitution effect Income 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. �� Copyright© 2004 South-Western

Menurunkan Kurva Permintaan (a) The Consumer’s Optimum (b) The Demand Curve for Pepsi Quantity of New budget constraint Ice Cream 750 Price of Ice Creami B $2 A I 2 250 B 1 A Demand I 1 0 Initial budget constraint Quantity of Coklat 0 250 750 Quantity 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. Copyright© 2004 South-Western