5.2: 边际效用

5.2 边际效用

边际效用

边际效用衡量的是一个人多消费一单位商品所得到的额外满足感。假设妮可（Nicole）非常饿，她点了一份披萨。她吃了第一块，这便给她带来了极大的满足感。这种满足感就是她吃第一块披萨的效用。接下来她又吃了一块披萨。在她吃第二片披萨时所额外得到的满足感就是它的边际效用。

边际效用递减规律

边际效用递减规律指出，在其他条件相同的情况下，当消费了足够数量的商品后，每消费一单位的商品所产生的效用都会递减。

例如，第一块披萨给妮可带来了非常高的满足感。但随着她继续吃更多的披萨，她的满足感会逐渐达到效用为零的阶段。最终，她的满足感将会达到效用为负的阶段，并使她不再想吃披萨了。

考虑一个女孩在烈日下骑摩托车，感到口渴。

她发现了一个加油站，买了一瓶水。第一瓶水给她带来了巨大的满足感或实用性。

她仍然口渴，又拿了一瓶水。

但是，它的效用小于第一个。

如果她喝更多的瓶装水，她可能会体验到负面的效用。

边际效用衡量一个人因多消费 1 单位商品而获得的额外满意度。

边际效用递减定律指出，在消费了足够数量的商品后，在所有其他条件相同的情况下，从每个连续单位得出的效用会减少。

消耗的水量按瓶子数的划分就是一个例子。实际上，商品可以分为数百或数千个单位。无论增量多么微小，每增加一个 good 单位，满意度就会降低，从而导致图表上的曲线连续递减。

• Marginal Utility - Measurement of satisfaction gained from consuming additional units of a commodity.
• Law of Diminishing Marginal Utility - Principle indicating decreased satisfaction provided by each successive unit consumed.
• Total Utility vs Marginal Utility - The relationship between overall satisfaction and incremental satisfaction.
• Marginal Utility Curve - Graphical representation of change in satisfaction against increased consumption.
• Negative Marginal Utility - Scenario where consumption of further units leads to a decrease in overall satisfaction.

• Define Marginal Utility – Understand the how and why it's obtained (e.g., measure of satisfaction)
• Contrast Total Utility vs Marginal Utility – Know how these two concepts are interrelated (e.g., satisfaction analysis)
• Explore Examples – Explain what happens when Nicole eats more pizza (e.g., diminishing satisfaction)
• Explain the Law of Diminishing Marginal Utility – Understand why satisfaction decreases with increased consumption
• Apply in Context - Understand how the concept helps in Consumer Behaviour Analysis.

• What is the difference between total utility and marginal utility?
• Why does marginal utility decrease with the consumption of more units?
• How does law of diminishing marginal utility affect consumer behaviour?

• Students – Can discover the correlation between consumption and satisfaction.
• Educators – Can illustrate the fundamentals of microeconomics regarding satisfaction.
• Researchers – Can examine consumer behaviour with regards to satisfaction.
• Economics Enthusiasts – Can understand key concepts of microeconomics and it's theories.