Luaran Pembelajaran

Setelah mempelajari materi ini, mahasiswa akan dapat:

1. Menjelaskan mengapa kemiringan kurva permintaan negatif.
2. Mengidentifikasi hal-hal yang dapat menggeser sebuah kurva permintaan ke kiri atau ke kanan.
3. Menjelaskan mengapa kemiringan kurva penawaran biasanya positif
4. Mengidentifikasi hal-hal yand dapat menggeser sebuah kurva penawaran ke kiri atau ke kanan
5. Menjelaskan mengapa di dalam kondisi pasokan barang berlimpah harga akan tertekan dan dalam kondisi pasokan langka harga akan terkerek.
6. Memprediksi dampak perubahan permintaan dan penawaran pada harga dan jumlah keseimbangan pasar.
7. Menjelaskan pengaruh penetapan harga dasar dan harga tertinggi oleh pemerintah pada pasar.

Permintaan

Berapa banyak risoles yang akan dibeli oleh mahasiswa perbulan jika harganya Rp 12.000/biji? Bagaimana jika harga naik menjadi Rp 15.000? atau turun ke Rp 10.000? Hubungan antara harga dengan jumlah permintaan risoles disebut dengan permintaan risoles.

Perhatikan permintaan mengindikasikan:

• Jumlah yang mau dan mampu dibeli oleh konsumen pada setiap harga selama waktu tertentu (the quantity consumers are both willing and able to buy at each price during a given time period, other things constant).

• Pada waktu tertentu: per hari, minggu, bulan (at a specific period—a day, a week, or a month).

• The emphasis on willing and able.

  • Anda mungkin mampu membeli sepeda Brompton baru yang harganya Rp 35 juta (saat ini dibuat, harganya sedang anjlok), tetapi mungkin Anda tidak mau membelinya karena tidak hobi bersepeda atau tidak sesuai dengan gaya hidup sederhana Anda.

Hukum Permintaan

The quantity of a good that consumers are willing and able to buy per period varies inversely, or negatively, with the price, other things equal.

• The higher the price, the smaller the quantity demanded;
• The lower the price, the greater the quantity demanded.

Dampak substitusi perubahan harga barang

Kelangkaan adalah hal riil

Jika tidak terjadi kelangkaan (mungkinkah ini terjadi?), maka barang-barang semuanya akan gratis:

• Bayangkan (contoh ekstrim) ketika dunia hanya dimiliki oleh Bapak Adam dan Ibu Hawa
• Bagaimana harga oksigen ketika puncak Covid-19 di Indonesia.

Apa yang menjelaskan hukum permintaan?

Mengapa jumlah yang diminta meningkat ketika harga barang turun?

• Ingat kembali: unlimited wants vs. scarce resources.
• Many goods and services can help satisfy particular wants: pingin kue bisa dipenuhi dengan bolu kukus, bikang, kue apem, nogosari, dll.

Kasus: Indonesia sangat kaya dengan keragaman jajanannya

• Lemper, pastel, kue lumpur, risoles, getuk, kue talam, cucur, bolu kukus, bikang, kue apem, nogosari, jemblem/gal-agil (bahasa daerah), onde-onde, dll.
• Bagaimana permintaan risoles jika harganya menjadi lebih mahal terhadap onde-onde?
• Bagaimana hubungan antara permintaan jenis-jenis kue itu satu sama lain?

Dampak substitusi perubahan harga kue

• The change in the relative price—the price of one good relative to the prices of other goods—causes the substitution effect.

• The higher opportunity cost causes some consumers to substitute other goods for the now more expensive risoles --> reducing the quantity of risoles demanded --> menggantinya dengan pastel.

• If all prices changed by the same percentage, there would be no change in relative prices and no substitution effect.

Dampak Pendapatan Perubahan Harga

• Pendapatan nominal.
  • The number of Rupiahs a person receives per period, such as Rp 6 million per month
• Pendapatan riil (real income Income)
  • Measured by the goods and services it can buy;
  • realincome changes when the price changes
• Dampak Pendapatan Perubahan Harga (Income effect of a price change)
  • A fall in the price of a good increases consumers’ real income,
  • Make consumers more able to purchase goods,
  • For a normal good, the quantity demanded increases
• Pertanyaan: kue bikang barang normal enggak?

Skedul Permintaan dan Kurva Permintaan

• Apa perbedaan keduanya?

• Kurva permintaan: A curve showing the relation between the price of a good and the quantity consumers are willing and able to buy per period, other things constant

• Price and quantity demanded are inversely related, other things constant, thus reflecting the law of demand.
• Jumlah diminta: the amount of a good consumers are willing and able to buy per period at a particular price, as reflected by a point on a demand curve.

Permintaan individu vs permintaan pasar

• Permintaan individu: the relation between the price of a good and the quantity purchased per period by an individual consumer, other things constant

• Permintaan pasar: the relation between the price of a good and the quantity purchased per period by all consumers in the market, other things constant --> sum of the individual demands in the market

Barang normal vs barang inferior

• Barang normal: A good, such as Indonesian snack, for which demand increases, or shifts rightward, as consumer income rises

• Barang inferior: A good, such as low quality snack, for which demand decreases, or shifts leftward, as consumer income rises. --> konsumen beralih ke jajanan yang bermutu lebih baik.

Pergeseran Kurva Permintaan

Hal-hal yang menggeser kurva permintaan:

• Pendapatan konsumen
• Harga barang-barang lain
• Selera konsumen
• Ekspektasi konsumen
• Komposisi dan/atau jumlah konsumen
• Apa lagi?
• Bagaimana jika yang berubah adalah harga barang itu sendiri?

Penawaran (supply)

• Supply indicates how much producers are willing and able to offer for sale per period at each possible price, other things constant.
• The law of supply states that the quantity supplied is usually directly related to its price, other things constant.
  • Thus, the lower the price, the smaller the quantity supplied;
  • The higher the price, the greater the quantity supplied.

Skedul Penawaran dan Kurva Penawaran

• Skedul penawaran:

• Kurva Penawaran: A curve showing the relation between price of a good and the quantity producers are willing and able to sell per period, other things constant.

• Quantity supplied refers to a particular amount offered for sale at a particular price, as reflected by a point on a supply curve.

Penawaran Individu dan Penawaran Pasar

• Penawaran Individu: the relation between the price of a good and the quantity an individual producer is willing and able to sell per period, other things constant.
• Penawaran Pasar: the relation between the price of a good and the quantity all producers are willing and able to sell per period, other things constant

Pergeseran Kurva Penawaran dan Pergerakan Sepanjang Kurva

Hal-hal yang menyebabkan pergeseran kurva penawaran:

• Teknologi yang semakin efisien
• Harga barang lain
• Harga input
• Harga barang itu sendiri? --> pergerakan
• Jumlah produsen
• Ekspektasi produsen

Pasar

DEMAND AND SUPPLY CREATE A MARKET

Ingat definisi Pasar sebelumnya: all the arrangements used to buy and sell a particular good or service.

• Keseimbangan Pasar (market equilibrium)
  • Market equilibrium occurs at the price where quantity demanded equals quantity sup- plied.
  • Perbedaan antara permintaan dan penawaran akan mendorong perubahan harga.
• Surplus at a given price: the amount by which quantity supplied exceeds quantity demanded; surplus biasanya akan menekan harga turun.
• Shortage at a given price: the amount by which quantity demanded exceeds quantity supplied; kekurangan pasokan (a shortage) biasanya akan mendorong harga naik.

Perubahan harga dan jumlah keseimbangan

Kurva akan ditunjukkan di kelas saat perkuliahan.

• Pergeseran kurva permintaan
• Pergeseran kurva penawaran
• Pergeseran keduanya
• Penetapan Harga maksimum
• Penetapan Harga minimum