Perfect competition

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Perfect competition발음듣기

In pretty much all of the videos so far we've been assuming an economic ideal, and that economic ideal is perfect competition.발음듣기

And perfect competition is exactly what you think it is, competition.발음듣기

But what I want to do in this video is think about it in a little bit more exact terms, in terms of what are the ground rules we need to have to really have this ideal perfect competition.발음듣기

It's important to realize that there's very few markets that are truly perfectly competitive.발음듣기

And those that are are very good for consumers, but there are that get very close to being perfectly competitive.발음듣기

And if we have time, we will discuss those in this video.발음듣기

Now, to be perfectly competitive, you have to have many competitors.발음듣기

So one of the first stipulations is many players.발음듣기

And they need to be competing for the kind of the same buyer and kind of offering the same thing.발음듣기

And so they need to have identical products.발음듣기

Remember, we're talking about an economic ideal here.발음듣기

There's very few markets where the product is absolutely identical or the service is absolutely identical, but we're talking about an economic ideal over here.발음듣기

The next condition you need is no barriers to entry.발음듣기

So, if at any given moment it looks attractive for other people to go into that market, other people will go into that market and there's nothing that's really going to stop them.발음듣기

If the firms that are already in the market are making an economic profit that means that it's good.발음듣기

It's a good option for people to do.발음듣기

You can do better in this market than your opportunity costs, and so people will enter into that market.발음듣기

And in order for this market to be perfectly competitive, we can't have any barriers, nothing stopping those people.발음듣기

On top of that, there can be no advantage for established firms.발음듣기

No advantage for existing firms.발음듣기

So once someone jumps into the fray and, assuming that they are somewhat competent, they are going to be able to compete on kind of equal terms with the people that are already there.발음듣기

And then the last one, and this is important, is that you have to have really good price information.발음듣기

That the buyers and the sellers all have to know about each other's prices.발음듣기

The buyers need to know all the prices so that they can really do good comparison shopping, and the sellers need to know everyone's prices so that they can really match prices really well.발음듣기

So good price information.발음듣기

Now, there are many different types of markets that somewhat approximate perfect competition.발음듣기

There are very few that are completely purely perfect competition.발음듣기

But one of them that does come to mind, one of them that does definitely come to mind is the US airline industry.발음듣기

And the US airlines - We can think about these different bullet points, how closely it matches it.발음듣기

There are definitely many different airlines.발음듣기

They don't offer identical products.발음듣기

I'm sure the airlines would not agree.발음듣기

They would say that they're differentiating on their service and what type of food they give or, I guess, don't give to you, or how much they're charging for the baggage check-in and all the rest.발음듣기

But for most consumers, they're just like, look, I just want an economy class ticket from San Francisco to New York, and they view them as almost identical products.발음듣기

So the airline industry does pretty well on this first point.발음듣기

No barriers to entry?발음듣기

Well, there are some barriers to entry in the airline industry.발음듣기

You need a few billion dollars that you need to either find or borrow or whatever, so that you can buy the capital so you can start operating planes.발음듣기

Or, I guess you could rent the planes.발음듣기

But, either way, you need a lot of capital to get into this business.발음듣기

You need access to airport terminals that you'll have to lease and landing rights and all the rest.발음듣기

So there are some barriers to entry.발음듣기

But for the most part, at least in the United States, if you are a US operator - so there are some barriers to entry, especially for foreign operators.발음듣기

But if you are a US operator and you have the capital you will be able to be the next Virgin America or Southwest Airlines or JetBlue.발음듣기

So there are some barriers to entry, but they are low.발음듣기

It's not like the government is saying that no one else can start a new airlines.발음듣기

No advantage for existing airlines?발음듣기

Yeah. That's somewhat true.발음듣기

If I start a new airlines tomorrow and it's offering comparable rates and comparable service, I could imagine people would be willing to take this airlines.발음듣기

So the airline industry seems pretty good there.발음듣기

And good price information - and this is why the airline industry definitely came to my mind, because I can't imagine an industry where you have better price information that at least now, after the internet came about - than in the airline industry you want a flight from San Francisco to New York, you go to any of these travel sites, Orbits, Kayak, Expedia, whatever you want to go to.발음듣기

And you get all of the flights listed for you and they're listed by price.발음듣기

They consort them by price.발음듣기

And you can actually pick - and it's known that people do this - they pick a flight that might be $500 or $600, but they can compare based on a few pennies or even a few dollars.발음듣기

So there's extremely good price information.발음듣기

And, obviously, the sellers have all of their IT systems, the airlines have all their IT systems to keep track of where airline prices are going as well.발음듣기

So the air travel industry, like most industries, is not absolutely perfect competition, but it gets pretty close to perfect competition.발음듣기

And you even see that in the real world, is that it's very hard for the airlines to make really a lot of profit, whether you're talking about accounting profit or even economic profit.발음듣기

And you can see that from this supply and demand curve right over here.발음듣기

So on this axis, the horizontal axis, this is the quantity.발음듣기

This is a measure of the quantity of kind of airline service.발음듣기

And we're measuring it in billions of seat miles per week, and I know that sounds like a strange thing.발음듣기

But really, we're just saying, OK, in a given week tell me all of the seats that are in use, and multiply those number of seats - so the seat miles in a given week.발음듣기

The number of seats times the miles or the average miles per seat in a given week, and that gives you how much air travel.발음듣기

This is a measure of air travel in, let's say, in the US in that week.발음듣기

And on this axis, this is the price.발음듣기

This is price per, and this should actually say price per seat mile.발음듣기

And, of course, you have your supply curve right over here.발음듣기

This is your supply curve.발음듣기

At first, to start providing those first few miles.발음듣기

The airlines are willing to do that relatively inexpensively.발음듣기

Maybe they're finding that from the most obvious airports that maybe the landing rights are cheaper or it's cheaper to lease things, or whatever.발음듣기

But as they start running more and more and more routes, maybe between smaller and smaller cities, maybe smaller and less efficient planes, it starts to become more and more expensive for them to supply those incremental miles.발음듣기

And obviously, on the demand side, if air travel is very, very expensive, very few people are going to want to travel.발음듣기

There is going to be very little travel that happens.발음듣기

If it's very cheap, many people are going to want to travel.발음듣기

Now, let's say that this is where the market is right now.발음듣기

Obviously, we have an equilibrium price right over there.발음듣기

And then we have an equilibrium quantity of seat miles.발음듣기

But let's say that the price level in order for the players to actually have an economic profit is over here.발음듣기

So it is right over here.발음듣기

So this is the price needed for zero economic profit, or you could say for neutral economic profit.발음듣기

Or you could even say for normal profit, for economic profit to be equal to zero.발음듣기

So at that point, if that is the price, then the firms that are offering airline travels, they're kind of neutral between shutting down and continuing to offer service.발음듣기

But notice, the way I've drawn it here that is substantially lower than the current equilibrium price.발음듣기

So what this is saying is since the current equilibrium price is a good bit higher than this, or it's just higher at all, these firms in the market right now are generating economic profit, definitely positive economic profit.발음듣기

So what's happening?발음듣기

If there is positive economic profit, that means that there's an incentive for other firms to enter into this industry.발음듣기

So what's going to happen is this is going to be the supply curve right at that moment.발음듣기

But as soon as another carrier realizes that they can, or any of the carriers realize they can offer more - it doesn't even have to be new carriers entering.발음듣기

It could be existing carriers just offering, maybe buying more planes or offering more routes.발음듣기

Then maybe a little bit later the supply curve shifts like this.발음듣기

The supply curve shifts like that.발음듣기

And then this would be our new equilibrium price.발음듣기

But we're still making economic profit because our new equilibrium price is still higher than the price needed for zero economic profit.발음듣기

So still more people will continue to enter.발음듣기

And so then you might have a new supply curve that looks like this.발음듣기

And now this is our new equilibrium price.발음듣기

And notice what's happening.발음듣기

We're traveling down to the right along the demand curve.발음듣기

As more supply comes on, we are obviously increasing the quantity and the price is going down.발음듣기

But still, the equilibrium price is higher than this line right over here.발음듣기

So even more people will enter, until we get to that point right over there.발음듣기

And at that point, now the equilibrium price is the price at which all of the players are having zero economic profit.발음듣기

And there's no incentive for more people to enter into it, because then the equilibrium price will go down, or they're, essentially right now economic profit is zero.발음듣기

So everyone is neutral in this scenario.발음듣기

So I want to leave you there.발음듣기

This is what happens with perfect competition.발음듣기

That there's no barriers to entry and more people go in and in and in, the price goes down, the quantity will go up in this scenario.발음듣기

But what I want to do in the next video is to think about what if we didn't have perfect competition.발음듣기

And especially, what happens if we have something like, I don't know, something like a monopoly.발음듣기

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