5.2
限界効用
限界効用は、財をもう 1 単位消費することで得られる追加の満足度を測定します。ニコールがお腹が空いていて、ピザを注文したとします。彼女は最初の1枚を食べ、大きな満足感を得ます。この満足感は、最初の1枚を消費することによる効用です。彼女はピザをもう1枚食べます。この2枚目を食べることで得られ…
暑い太陽の下、喉が渇いていると感じている女の子を考えてみてください。
ガソリンスタンドを見つけた彼女は、ボトル入りの水を買う。この最初のボトル入り飲料水は、彼女に計り知れない満足感や有用性を与えてくれます。
まだ喉が渇いていたので、彼女は別のボトル入りの水を手に入れます。
ただし、これの有用性は最初のものよりも劣ります。
彼女がより多くのボトル入り飲料水を飲むと、彼女はマイナスの効用を経験する可能性があります。
限界効用は、商品のもう1単位を消費することによる人の追加の満足度を測定します。
限界効用逓減の法則は、十分な量の商品が消費された後、他のすべての条件が等しい場合、各連続する単位から得られる効用が減少すると述べています。
ボトルの数で消費される水の分割は一例です。実際には、商品は数百または数千のユニットに分割される可能性があります。どんなに小さな増分でも、善の単位が追加されるたびに満足度が低くなり、グラフ上の曲線が連続的に減少します。
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Q1: What does marginal utility measure in consumer behavior?
Marginal utility measures the additional satisfaction a person gains from consuming one more unit of a commodity. For example, the first bottle of water provides immense satisfaction to a thirsty person, while the second bottle provides less additional satisfaction. Understanding marginal utility helps explain how consumer satisfaction changes with each additional unit consumed.
Q2: Why does satisfaction decrease with each additional unit consumed?
The law of diminishing marginal utility states that after consuming a sufficient quantity of a commodity, the utility from each successive unit decreases, all other things being equal. As a person consumes more pizza slices, each additional slice provides less satisfaction than the previous one, eventually reaching zero or negative utility.
Q3: How does the relationship between total utility and marginal utility work?
Total utility is the cumulative satisfaction from all units consumed, while marginal utility is the satisfaction from one additional unit. The relationship between total utility and marginal utility shows that as marginal utility decreases, total utility continues to increase but at a slower rate until marginal utility becomes negative.
Q4: Can marginal utility ever become negative?
Yes, marginal utility can become negative when consuming additional units actually decreases overall satisfaction. For instance, after eating many pizza slices, consuming more may cause discomfort, resulting in negative utility. This explains why consumers eventually stop purchasing additional units of a good.
Q5: How does marginal utility apply to real-world consumer decisions?
Consumers use marginal utility concepts when deciding whether to purchase additional units. A motorcycle rider buys water bottles based on the satisfaction each provides. Once marginal utility becomes low or negative, the consumer stops buying, which influences demand patterns and purchasing behavior in markets.
Q6: Does the size of consumption units affect marginal utility?
No, the principle of diminishing marginal utility applies regardless of unit size. Whether goods are divided into large or tiny increments, each additional unit provides less satisfaction than the previous one. This creates a continuous diminishing curve on a graph, illustrating the universal nature of this economic principle.