Disequilibrium and Changes in Equilibrium · 非均衡与均衡的变动
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| surplus/ˈsɜːpləs/ | 过剩 | guò shèng |
| shortage/ˈʃɔːtɪdʒ/ | 短缺 | duǎn quē |
| indeterminate/ˌɪndɪˈtɜːmɪnət/ | 不确定 | bù què dìng |
| simultaneous shift/ˌsɪməlˈteɪnɪəs ʃɪft/ | 同时移动 | tóng shí yí dòng |
Too high, too low, or just right
- Leave a market alone and it drifts toward one special price.
- Set the price too high and unsold goods pile up; too low and buyers fight over too little.
- Either way, pressure builds that pushes the price back.
- Understanding that pressure lets you predict where a market will land.
太高、太低,还是刚刚好
- 让市场自己运行,它会朝一个特别的价格漂移。
- 价格定得太高,卖不掉的货就堆积;太低,买家就为太少的货争抢。
- 无论哪种,都会积累出把价格推回去的压力。
- 弄懂这种压力,你就能预测市场会停在哪里。
Surplus and shortage
- Above equilibrium: quantity supplied exceeds quantity demanded — a surplus 过剩 (excess supply). Sellers cut prices.
- Below equilibrium: quantity demanded exceeds quantity supplied — a shortage 短缺 (excess demand). Buyers bid prices up.
- So a free market self-corrects: a surplus pushes the price down, a shortage pushes it up.
过剩与短缺
- 高于均衡:供给量大于需求量——出现过剩(surplus,即超额供给)。卖家降价。
- 低于均衡:需求量大于供给量——出现短缺(shortage,即超额需求)。买家抬价。
- 所以自由市场会自我纠正:过剩把价格压下去,短缺把价格顶上来。
If the price is set above the equilibrium, the market has a: · 如果价格定在均衡之上,市场会出现:
Above equilibrium, quantity supplied exceeds quantity demanded — a surplus, so sellers cut prices. · 高于均衡时,供给量超过需求量——过剩,于是卖家降价。
When the price is below equilibrium, excess demand creates a . · 当价格低于均衡时,超额需求造成一个。
A shortage pushes buyers to bid the price up toward equilibrium. · 短缺促使买家抬高价格,回到均衡。
One shift moves the equilibrium
- When a determinant changes, a curve shifts and equilibrium moves. Trace it in two steps.
- Demand right: price up, quantity up. Demand left: price down, quantity down.
- Supply right: price down, quantity up. Supply left: price up, quantity down.
一次移位就移动均衡
- 当某个决定因素变化,一条曲线移位,均衡随之移动。分两步追踪。
- 需求右移:价格上升,数量上升。需求左移:价格下降,数量下降。
- 供给右移:价格下降,数量上升。供给左移:价格上升,数量下降。
Shift a curve, move the equilibrium · 移动一条曲线,均衡随之改变
Change a determinant and one curve shifts, moving the equilibrium to a new price and quantity. Try each shift and read the new crossing point. · 改变一个决定因素,一条曲线就移位,把均衡移到新的价格和数量。试试每种移位,读出新的相交点。
Demand shifts right (supply unchanged). Price and quantity: · 需求右移(供给不变)。价格和数量:
A rightward demand shift raises both the equilibrium price and quantity. · 需求右移使均衡价格和数量都上升。
Put the steps to find a new equilibrium after a change in order. · 把变化后求新均衡的步骤按顺序排列。
Name the shifter, move the right curve the right way, then read the new crossing point. · 先说出移位因素,把正确的曲线朝正确方向移动,再读出新的相交点。
Select all · 所有 single shifts that raise the equilibrium price. · 选出所有会提高均衡价格的单次移位。
Demand-right and supply-left both raise price; the other two lower it. · 需求右移和供给左移都提高价格;另外两个则降低价格。
When both curves shift
- If demand and supply move at once, one result is clear and the other is indeterminate 不确定 — it depends on which shift is bigger.
- Demand right and supply right → quantity definitely rises; price is indeterminate.
- Demand right and supply left → price definitely rises; quantity is indeterminate.
With a simultaneous shift 同时移动, always sketch both moves. The diagram fixes one variable but cannot fix the other without knowing the sizes of the two shifts.
当两条曲线同时移动
- 如果需求和供给同时移动,一个结果明确,另一个则不确定(indeterminate)——取决于哪次移位更大。
- 需求右移且供给右移 → 数量必定上升;价格不确定。
- 需求右移且供给左移 → 价格必定上升;数量不确定。
遇到同时移动(simultaneous shift),一定把两次移动都画出来。图能确定一个变量,但在不知道两次移位大小的情况下无法确定另一个。
When both demand and supply shift at once, both price and quantity are always determinate. · 当需求和供给同时移位时,价格和数量总是都能确定。
One is determinate; the other depends on which shift is larger — it is indeterminate. · 一个可以确定;另一个取决于哪次移位更大——它是不确定的。
Above equilibrium sits a surplus, below it a shortage, and the price self-corrects. A single shift moves both price and quantity predictably; a simultaneous shift pins down only one of them — the other is indeterminate.
均衡上方是过剩,下方是短缺,价格会自我纠正。单次移位可预测地移动价格和数量;同时移动只能确定其中一个——另一个是不确定的。