Is it a science?

 Economics is the study of choices forced by scarcity  Almost all economic choices involve opportunity costs

 It involves taking measurements (DATA)  Building models  And making predictions (HYPOTHESES)

 Is the market value of all final goods and services produced within a nation in one year.  USA GDP 2011:  $15,300,000,000,000

 Unemployment is calculated as a percentage by dividing the number of unemployed individuals by all individuals currently in the labor force  August 2012: 8.3%

 measures changes in the price level of consumer goods and services purchased by households.  A more common phrase is inflation rate.  2011: 3.2%

 1. the average weekly hours worked by manufacturing workers  2. the average number of initial applications for unemployment insurance  3. the amount of manufacturers' new orders for consumer goods and materials  4. the speed of delivery of new merchandise to vendors from suppliers  5. the amount of new orders for capital goods unrelated to defense  6. the amount of new building permits for residential buildings  7. the S&P 500 stock index  8. the inflation-adjusted monetary supply (M2)  9. the spread between long and short interest rates  10. consumer sentiment

 The entire discipline is dependent on a massive variable:  HUMAN BEHAVIOR