Question 1 — Loanable Funds and Interest Rate (可贷资金与利率)
The market for loanable funds has supply S: r = 2 + 0.002Q and demand D: r = 8 − 0.001Q (r in %, Q in billions).
Find the equilibrium real interest rate and the amount of funds lent.
可贷资金市场的供给与需求为：S：r = 2 + 0.002Q，D：r = 8 − 0.001Q（r 为利率%，Q 为十亿美元）。
求市场均衡的实际利率与资金数量。
📖 点击查看答案
r* = 6%, Q* = 2,000 billion.
📝 点击查看解析
均衡条件：2 + 0.002Q = 8 − 0.001Q → 0.003Q = 6 → Q = 2,000。
代回得 r = 6%。市场利率6%，可贷资金总额2,000亿美元。
Question 2 — Government Deficit (政府赤字)
If the government runs a budget deficit of $200 billion, what happens to the supply curve of loanable funds and the equilibrium interest rate?
若政府出现2000亿美元赤字，可贷资金供给曲线和均衡利率会如何变化？
📖 点击查看答案
Supply shifts left; equilibrium interest rate rises; quantity of funds falls.
📝 点击查看解析
政府赤字减少公共储蓄，使可贷资金供给曲线左移。供给减少导致利率上升、资金数量下降。称为“挤出效应”。
Question 3 — Fiscal Expansion (财政扩张)
The government increases spending by 5% while holding taxes constant.
Explain how this affects investment and interest rates in the loanable funds market.
政府支出上升5%，税收不变。说明对投资与利率的影响。
📖 点击查看答案
Higher interest rates, lower investment (crowding out).
📝 点击查看解析
财政扩张减少公共储蓄，使供给曲线左移。利率上升、投资下降，形成挤出效应。
Question 4 — Economic Growth and Saving Rate (经济增长与储蓄率)
Country A saves 25% of GDP, Country B saves 15%. Assuming similar productivity, which country experiences faster long-run growth?
国家A储蓄率25%，国家B储蓄率15%。假设生产率相似，哪国长期增长更快？
📖 点击查看答案
Country A grows faster.
📝 点击查看解析
较高储蓄率提高资本形成，促进长期增长。A国资本积累更快，因此长期增长率较高。
Question 5 — Productivity Shock (生产率冲击)
If technological progress increases productivity by 4%, how does it affect potential GDP and unemployment in the long run?
若技术进步使生产率提高4%，长期潜在GDP与失业率将如何变化？
📖 点击查看答案
Potential GDP increases; natural unemployment decreases slightly.
📝 点击查看解析
生产率上升使潜在产出提高，长期可持续增长。劳动力需求增加，自然失业率略降。
Question 6 — Loanable Funds Shock (可贷资金冲击)
A fall in household saving due to higher consumption reduces supply of loanable funds by $100 billion.
Illustrate the direction of change for equilibrium interest rate and investment.
家庭消费上升导致储蓄减少1000亿美元。说明均衡利率与投资的变化方向。
📖 点击查看答案
Interest rate rises; investment decreases.
📝 点击查看解析
储蓄下降 → 供给曲线左移 → 均衡利率上升 → 投资下降。
Question 7 — Recession and Output Gap (衰退与产出缺口)
If actual GDP is 20 trillion, what type of gap exists and what policy should government use?
若实际GDP为18万亿美元，潜在GDP为20万亿美元，存在何种缺口？政府应采取何种政策？
📖 点击查看答案
Recessionary gap; use expansionary fiscal or monetary policy.
📝 点击查看解析
实际产出低于潜在产出 → 衰退缺口。应采取扩张性财政（增支减税）或货币政策（降息）刺激经济。
Question 8 — Inflationary Gap (通胀缺口)
If actual GDP = 20 trillion, what gap exists and what policy is suitable?
若实际GDP为22万亿，潜在GDP为20万亿，应采取何政策？
📖 点击查看答案
Inflationary gap; contractionary policy is needed.
📝 点击查看解析
实际产出超过潜在产出 → 通胀缺口。应采取紧缩性政策，如提高利率或削减支出。
Question 9 — Business Cycle Phase (经济周期阶段)
During which phase of the business cycle do inflation and wages typically rise faster than prices?
在经济周期的哪个阶段，通胀和工资通常上涨快于价格？
📖 点击查看答案
At the end of expansion.
📝 点击查看解析
扩张末期：产能趋满，工资和利率上升，企业成本上升，利润压缩。
Question 10 — Unemployment Dynamics (失业动态)
During recovery, why does unemployment often fall more slowly than GDP rises?
在经济复苏期，为什么失业率下降速度慢于GDP上升？
📖 点击查看答案
Firms wait to confirm sustained demand before rehiring workers.
📝 点击查看解析
企业在初期复苏阶段谨慎，先使用现有员工，提高产能利用率，待需求稳定后才扩招，因此失业回落滞后。
Question 11 — Inflation Measurement (通胀衡量)
If the CPI rises from 120 to 126 in one year, what is the inflation rate?
若CPI从120升至126，通胀率是多少？
📖 点击查看答案
Inflation = (126 − 120) / 120 = 5%.
📝 点击查看解析
通胀率计算公式：(新CPI − 旧CPI) ÷ 旧CPI × 100% = 5%。
Question 12 — Real vs. Nominal Interest Rate (名义与实际利率)
If nominal interest rate = 7% and inflation = 3%, what is the real interest rate?
名义利率7%，通胀率3%，求实际利率。
📖 点击查看答案
Real rate = 7% − 3% = 4%.
📝 点击查看解析
实际利率 = 名义利率 − 通胀率 = 4%。
Question 13 — Crowding Out in Numbers (数值化挤出效应)
Investment demand: r = 10 − 0.5I; Supply: r = 2 + 0.25I.
If government deficit shifts supply to r = 3 + 0.25I, compute equilibrium before and after.
投资需求：r = 10 − 0.5I；供给：r = 2 + 0.25I。
赤字使供给变为 r = 3 + 0.25I。求均衡利率与投资。
📖 点击查看答案
Before: I=10.67, r=4.67%. After: I=9.33, r=5.67%.
📝 点击查看解析
均衡：10 − 0.5I = 2 + 0.25I → I=10.67, r=4.67%。
赤字后：10 − 0.5I = 3 + 0.25I → I=9.33, r=5.67%。利率升高，投资减少。
Question 14 — Output and Unemployment (产出与失业)
If potential GDP grows 3% per year but actual GDP grows 1%, what happens to unemployment?
潜在GDP年增3%，实际仅增1%，失业将如何变化？
📖 点击查看答案
Unemployment rises (Okun’s law).
📝 点击查看解析
根据奥肯定律，实际增长低于潜在增长意味着产出缺口扩大，失业上升。
Question 15 — Business Confidence (企业信心)
A rise in business confidence increases investment by 15%. Explain the effect on GDP and employment.
企业信心上升使投资增加15%。说明对GDP和就业的影响。
📖 点击查看答案
GDP and employment increase due to multiplier effect.
📝 点击查看解析
投资上升提高总需求，带动GDP与就业增长。乘数效应放大初始投资影响。
Concept Question 1 — Define Loanable Funds Market (定义可贷资金市场)
📖 点击查看答案
The market where savers supply funds and borrowers demand funds for investment.
📝 点击查看解析
可贷资金市场是储蓄者提供资金、借款者为投资需求资金的市场，决定均衡利率。
Concept Question 2 — Explain “Crowding Out” (解释挤出效应)
📖 点击查看答案
When government borrowing increases interest rates, reducing private investment.
📝 点击查看解析
政府为融资赤字而借款，推高利率，从而抑制私人投资，即“挤出效应”。
Concept Question 3 — Define Recession (定义衰退)
📖 点击查看答案
A period of declining GDP and employment lasting for at least two consecutive quarters.
📝 点击查看解析
衰退是GDP与就业连续两个季度下降的经济阶段。
Concept Question 4 — Define Potential GDP (定义潜在GDP)
📖 点击查看答案
The level of output produced when the economy operates at full employment.
📝 点击查看解析
潜在GDP指经济在充分就业下可实现的最大可持续产出水平。
Concept Question 5 — Define Natural Rate of Unemployment (定义自然失业率)
📖 点击查看答案
The normal unemployment rate including frictional and structural unemployment.
📝 点击查看解析
自然失业率包括摩擦性与结构性失业，是经济在长期均衡下的正常失业水平。