Supply and demand theory

[Cornfed]

Just a random thought. What is the evidence for the economic theory that supply and demand curves for items exist and the market price for an item is where the curves intersect? It seems to me that in order to demonstrate this you would have to run experiments where you mandated different prices for items and observed the supply and demand at that price, and as far as I know nobody does this. Probably the whole idea is complete fiction and it is more a case of the labour theory of value being largely correct for prices overall over time, with individual transactions being influenced by many factors.

[MrMan]

Just a random thought. What is the evidence for the economic theory that supply and demand curves for items exist and the market price for an item is where the curves intersect? It seems to me that in order to demonstrate this you would have to run experiments where you mandated different prices for items and observed the supply and demand at that price, and as far as I know nobody does this. Probably the whole idea is complete fiction and it is more a case of the labour theory of value being largely correct for prices overall over time, with individual transactions being influenced by many factors.

There are plenty of products that sell like commodities and lots of data on them. If there were nothing to the theory, it would be overthrown. Theories only roughly represent the real world, typically, but some of them generally tend to be true.

Go into scholar.google.com and look it up.

[Cornfed]

If there were nothing to the theory, it would be overthrown.

Classic appeal to authority fallacy and not addressing the issue/.

[MrMan]

If there were nothing to the theory, it would be overthrown.

Classic appeal to authority fallacy and not addressing the issue/.

You may have a valid point with that. It isn't the strongest argument. I can see evidence for supply and demand and it is intuitive, also. If you were locked in an office building and the water were shut down, with North Korean invaders on the streets, and there were 10 water bottles left in the convenience store in the building, do you think the price would go up?

You can dig through Google Scholar. If you dig deep enough, you will find something. Most papers on the topic have to do with exceptions or niche applications of supply and demand, not proving the basic theory.

That much should not be debated because it is so obvious. As far as the details of Alfred Marshall's theories and formulas are concerned, you could go look up some empirical pieces from history that use the formulas and examine the data in Google scholar. You can search for years between 1890 and say the 1930's... or maybe a bit later as stats began to be more widely used in research.