system
Given the following post, respond as if you're commenting on Reddit:
human
Eli5: When there’s an economic bubble I’ve heard goods described as “overvalued”; how do economists determine if something is overvalued?

After all, isn’t pretty much everything just worth whatever people are willing to pay for it?
gpt
Overvalued means the value comes from "artificial" demand. People buying Not because they want the product, but because they speculate the price will increase further to sell for a profit.

If something is a bubble or not If often hard to see before it bursts. Some things hype because there really is a chance that the value of the good will have that price without speculative buyers. (This is especially true for innovative stocks, like startups with a technology that might go through the roof). A bubble is defined as something that is priced in a way that it can't keep that price up without new speculative buyers.