Seni Ilmu Analisis Ekonomi Permasalahan Ekonomi Kepentingan Pribadi

Seni & Ilmu Analisis Ekonomi • Permasalahan Ekonomi • Kepentingan Pribadi yang Rasional • Analisis Marginal • Metoda Ilmiah • Kelemahan Pemikiran Ekonomi Sumber: Mc. Eachern, Ek. Makro, Pendekatan Kontemporer

PERMASALAHAN EKONOMI : SUMBER DAYA TERBATAS TAPI KEINGINAN TAK TERBATAS Barang & Jasa Keinginan/ kebutuhan Kelangkaan Pilihan Sumber Daya Imbalan Sumber Daya Sumber: Mc. Eachern, Ek. Makro, Pendekatan Kontemporer

Objek nyata yang digunakan untuk memenuhi keinginan & Kegiatan yg ditujukan utk memenuhi keinginan Barang dan Jasa & Tenaga Kerja Kapital Tanah Kewirausahaan Konsekwensi kelangkaan Upah Laba Bunga Sewa Sumber: Mc. Eachern, Ek. Makro, Pendekatan Kontemporer Bila jumlah yang diinginkan orang melebihi jumlah yang tersedia pada harga sebesar nol

Pelaku Ekonomi Rumah Tangga Perusahaan Pemerintah Luar Negeri Pasar Analisis Mikro & Makro Pasar Barang & Jasa & Pasar Sumber Daya / Faktor Produksi Sumber: Mc. Eachern, Ek. Makro, Pendekatan Kontemporer

Analisis Ekonomi Rational Self Interest: Expected Cost Expected Benefit Analisis Marginal : Expected Marginal Cost Expected Marginal Benefit Pilihan Memerlukan Waktu & Informasi Analisis Positif dan Normatif Sumber: Mc. Eachern, Ek. Makro, Pendekatan Kontemporer

Ilmu dari Analisis Ekonomi Teori/Model Ekonomi : Penyederhanaan dari kenyataan ekonomi yang digunakan untuk membuat perkiraan atas dunia nyata Metoda Ilmiah: 1. Identifikasi Pertanyaaan dan Penentuan Variabel 2. Spesifikasi Asumsi & Asumsi Perilaku 4. Hipotesa 5. Validitas Prediksi rata-rata Perilaku Sumber: Mc. Eachern, Ek. Makro, Pendekatan Kontemporer

Exhibit 2 The Scientific Method 1. Identify the Question and Define Relevant Variables 2. Specify Assumptions Modify Approach 3. Formulate a hypothesis 4. Test the hypothesis or Reject the hypothesis Use the hypothesis until a better one shows up 7

Beberapa Kelemahan Analisis Ekonomi The Fallacy of Composition Efek Sekunder Association is Causation Sumber: Mc. Eachern, Ek. Makro, Pendekatan Kontemporer

Appendix Understanding Graphs § § § Origin Horizontal axis Vertical axis Graph Functional relation – Dependent variable – Independent variable

Exhibit 4 Vertical axis Basics of a Graph y 20 Point a: - 5 units X - 15 units Y a 15 Point b: - 10 units X - 5 units Y 10 b 5 0 Origin 5 10 15 x 20 Horizontal axis

Exhibit 5 U. S. Unemployment Rate Since 1900

Appendix Drawing Graphs § Dependent variable – Depends on the independent variable § Types of relations between variables – Positive; direct – Negative; inverse – Independent; unrelated

Exhibit 6; Exhibit 7 Hours Distance Driven Traveled per Day (miles) a b c d e 1 2 3 4 5 50 100 150 200 250 Points a through e depict different combinations of hours driven per day and the corresponding distances traveled. Connecting these points graphs a line. Distance traveled per day (miles) Schedule and Graph Relating Distance Traveled to Hours Driven 250 e 200 d 150 c 100 b 50 0 a 1 5 2 4 3 Hours driven per day

Appendix Slopes of Straight Lines § Slope – Change in vertical variable – For a given increase in horizontal variable § Slope = Change in the vertical distance/ Increase in the horizontal distance § Slope of a straight line – The same value along the line

Exhibit 8(a), (b) Alternative Slopes for Straight Lines (b) Negative relation (a) Positive relation y y 20 20 Slope = 5/10 = 0. 5 15 Slope = - 7/10 = - 0. 7 5 10 10 10 -7 3 10 0 10 20 x

Exhibit 8(c), (d) Alternative Slopes for Straight Lines (d) No relation: infinite slope (c) No relation: zero slope y y 20 20 Slope = 10/0 = ∞ 10 Slope = 0/10 = 0 10 10 10 20 x 0 10 x

Appendix Slope, Units of Measurement, Marginal Analysis § Value of slope – Depends on units of measurement – Measures marginal effects

Exhibit 9 Slope Depends on the Unit of Measure Total cost $6 (a) Measured in feet Slope = 1/1 =1 1 5 1 (b) Measured in yards Total cost $6 Slope = 3/1 =3 3 3 1 0 5 6 Feet of copper tubing 0 1 2 Yards of copper tubing (a) Output is measured in feet of copper tubing. (b) Output is measured in yards. The cost: $1 per foot. Slope is different: copper tubing is measured using different units

Appendix The Slopes of Curved Lines § Differs along the curve § Slope of a curved line at one point – Slope of the tangent

Exhibit 10 Slope at Different Points on a Curved Line y 40 The slope of a curved line varies from point to point. A 30 At point a, the slope of the curve is equal to the slope of the tangent A. a 20 At point b, the slope of the curve is equal to the slope of the tangent B. B 10 b 0 10 20 30 x 40

Exhibit 11 Curves with Both Positive and Negative Slopes Some curves have both positive and negative slopes. y a b 0 The U-shaped curve has: negative slope to the left of b slope of 0 at point b positive slope to the right of b. The hill-shaped curve has: positive slope to the left of a slope of 0 at point a x negative slope to the right of a.

Appendix Line Shifts § Change assumptions – Changed relationship between variables – Line shift

Distance traveled per day (miles) Exhibit 12 Shift of Line Relating Distance Traveled to Hours Driven T 250 d 200 f Line T T’ hours driven/day and distance traveled/day average speed = 50 mph 150 Line T’ hours driven/day and distance traveled/day average speed = 40 mph 100 50 0 1 2 5 4 3 Hours driven per day