Short-Run Aggregate Supply (SRAS) · 短期总供给（SRAS）
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| aggregate supply/ˈæɡrɪɡeɪt səˈplaɪ/ | 总供给 | zǒng gōng jǐ |
| short-run aggregate supply/ʃɔːt rʌn ˈæɡrɪɡeɪt səˈplaɪ/ | 短期总供给 | duǎn qī zǒng gōng jǐ |
| sticky/ˈstɪki/ | 粘性 | zhān xìng |
| nominal wages/ˈnɒmɪnl ˈweɪdʒɪz/ | 名义工资 | míng yì gōng zī |
| input prices/ˈɪnpʊt ˈpraɪsɪz/ | 投入品价格 | tóu rù pǐn jià gé |
| productivity/ˌprɒdəkˈtɪvɪti/ | 生产率 | shēng chǎn lǜ |
| supply shocks/səˈplaɪ ʃɒks/ | 供给冲击 | gōng jǐ chōng jī |
| inflationary expectations/ɪnˈfleɪʃənəri ekspɪkˈteɪʃnz/ | 通货膨胀预期 | tōng huò péng zhàng yù qī |
| negative supply shock/ˈneɡətɪv səˈplaɪ ʃɒk/ | 负面供给冲击 | fù miàn gōng jǐ chōng jī |
What firms will produce — for now
- Aggregate demand is only half the picture; supply is the other half.
- Aggregate supply 总供给 is how much output firms will make at each price level.
- In the short run, it slopes upward — a higher price level brings more output.
- This is the short-run aggregate supply 短期总供给 (SRAS) curve.
企业愿意生产多少——暂时而言
- 总需求只是一半;供给是另一半。
- 总供给(aggregate supply)是企业在每个价格水平下愿意生产多少。
- 在短期,它向上倾斜——更高的价格水平带来更多产出。
- 这就是短期总供给(short-run aggregate supply,SRAS)曲线。
Why SRAS slopes up: sticky wages
- In the short run, some costs are sticky 粘性 — fixed by contracts and slow to change.
- The clearest is nominal wages 名义工资, the dollar wages set in labour contracts.
- When the price level rises but wages stay locked in, profit per unit rises — so firms produce more.
- A higher price level therefore brings more output: an upward slope.
SRAS 为什么向上:粘性工资
- 在短期,有些成本是粘性(sticky)的——由合同固定,变化缓慢。
- 最典型的是名义工资(nominal wages),即劳动合同里定下的以货币计的工资。
- 当价格水平上升而工资仍被锁定,单位利润上升——于是企业多生产。
- 因此更高的价格水平带来更多产出:向上的斜率。
The AD-AS model · 总需求—总供给模型
SRAS slopes up because wages are sticky in the short run. Dearer inputs shift it left (raising prices, cutting output); better productivity shifts it right. · SRAS 向上倾斜,因为短期工资粘性。投入更贵使它左移(抬价、减产);生产率更高使它右移。
SRAS slopes upward mainly because, in the short run: · SRAS 向上倾斜,主要因为在短期:
With wages locked in, a higher price level means more profit per unit, so firms produce more. · 工资被锁定时,更高的价格水平意味着更多单位利润,所以企业多生产。
Costs that are fixed by contracts and slow to change in the short run are called . · 在短期由合同固定、变化缓慢的成本被称为。
Sticky nominal wages are the key reason SRAS slopes upward. · 粘性名义工资是 SRAS 向上倾斜的关键原因。
What shifts SRAS
- Input prices 投入品价格 (wages, energy, raw materials): higher input prices shift SRAS left.
- Productivity 生产率: higher output per worker shifts SRAS right.
- Supply shocks 供给冲击 and inflationary expectations 通货膨胀预期 shift it too.
什么会移动 SRAS
- 投入品价格(input prices,工资、能源、原材料):投入品价格更高使 SRAS 左移。
- 生产率(productivity):每个工人产出更高使 SRAS 右移。
- 供给冲击(supply shocks)和通货膨胀预期(inflationary expectations)也会移动它。
A rise in input prices (like energy) shifts SRAS: · 投入品价格(如能源)上升使 SRAS:
Dearer inputs make production costlier at every price level, shifting SRAS left. · 更贵的投入使每个价格水平下生产更贵,SRAS 左移。
Select all · 所有 that shift SRAS to the right · 精准的. · 选出所有使 SRAS 右移的因素。
Cheaper inputs, higher productivity and positive shocks raise SRAS; dearer oil shifts it left. · 更便宜的投入、更高生产率和正面冲击提高 SRAS;油价上涨使它左移。
Higher productivity lowers the cost of each unit and shifts SRAS right. · 更高的生产率降低每单位成本,使 SRAS 右移。
More output per worker means cheaper production, so firms supply more at every price level. · 每个工人产出更多意味着生产更便宜,所以企业在每个价格水平下供给更多。
A supply shock
- Worked idea. World oil prices double. Oil is an input for transport, plastics, and power, so costs rise across the whole economy — a negative supply shock 负面供给冲击.
- SRAS shifts left: less output is supplied at every price level.
- The price level rises and output falls at the same time.
- A positive shock (cheaper inputs) does the reverse, shifting SRAS right.
一次供给冲击
- 例题。 世界石油价格翻倍。石油是运输、塑料和电力的投入,所以全经济范围内成本上升——一次负面供给冲击(negative supply shock)。
- SRAS 左移:每个价格水平下供给的产出更少。
- 价格水平上升同时产出下降。
- 正面冲击(更便宜的投入)则相反,使 SRAS 右移。
A negative supply shock (say, oil prices double) causes: · 一次负面供给冲击(比如油价翻倍)造成:
SRAS shifts left, so along AD the price level rises while output falls — a preview of stagflation. · SRAS 左移,所以沿 AD,价格上升、产出下降——滞胀的预演。
SRAS slopes up because nominal wages are sticky — a higher price level lifts profit per unit, so firms produce more. It shifts with input prices, productivity, and supply shocks: a negative shock (dearer inputs) shifts SRAS left, raising prices while cutting output.
SRAS 向上倾斜,因为名义工资是粘性的——更高的价格水平抬升单位利润,所以企业多生产。它随投入品价格、生产率和供给冲击移动:负面冲击(投入更贵)使 SRAS 左移,抬高价格同时削减产出。