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Who else is affected by a transaction?

A purchase can have consequences for people who were neither the buyer nor the seller. Economists call such outside costs or benefits externalities; identifying one still leaves questions about its size and what, if anything, should be done.

3–5 min

Questions you could explore

  • What makes an effect external to the exchange?
  • How would you distinguish identifying an effect from measuring it?

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Economics and money

Why can Ireland’s inflation rate differ from your shopping bill?

A national price index combines many purchases that no single household makes in exactly the same proportions. Ireland's Consumer Price Index uses spending weights, so changes in different prices contribute unequally to the overall figure.

4–5 min
Economics and money

What does a free afternoon still cost you?

An hour can be free of charges and still be scarce. Choosing one use means giving up the best available alternative, which is the opportunity cost even when no money changes hands.

3–5 min
Economics and money

How can insurance spread financial risk across a group?

An uncertain large loss for one person can become part of a wider pool of risks. Insurance connects that pooling with a contract and a premium, while the contract still determines which losses are covered.

3–7 min
Who else is affected by a transaction? | Speech Topic | speaking.app