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Monopoly price discrimination

Price discrimination is charging each consumer their entire willingness to pay. What if a monopolist can charge each buyer their entire willingness to pay? Learn about the effect of perfect price discrimination on output and deadweight loss in this video.

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Video transcript

- [Instructor] Let's say that you own the only hotel that is in a city, and for a wide variety of reasons, maybe all of the city council members are your friends or whatever else, no one else can build a hotel in the city. So there are insurmountable barriers to entry. So in that situation, you would have a monopoly. You are the only player in the market, and there are very, very high barriers to entry. Now, this is a typical cost structure and demand curve for a monopoly. We've already talked about your marginal cost. It might dip down a little initially, but then it might go up, and we could debate whether that would be true for a hotel or not, but this is a typical model we see. And then while your marginal cost is below average total cost, average total cost trends down, and then hits a minimum point where marginal cost intersects it, and then it starts to trend up as marginal cost is higher than that. And the demand curve for a monopoly looks familiar. When the prices are high, if the prices on the hotel rooms per night are high, very few people will demand them, and if the prices are low, a lot of folks would demand them. Now something that we've talked about in a lot of detail in other videos is how the marginal revenue curve is different than the demand curve for a monopoly. And that's because, if you were to charge a price of, let's say, $500 per room, you might be able to get one room rented out for the night but no other rooms. And if you wanted to get two rooms rented out, well, you would have to charge $400, not just for that room. So now we'd get a little bit further down this demand curve. When you charge $400 maybe for that second room, because someone's willingness to pay is $400. Well you might have to also charge $400 for that first room. So in many monopoly industries, whatever you charge to one consumer, you have to charge to other consumers. Now, I know what some of you are thinking, hey, that doesn't always happen in a hotel, and that's why I picked this example. Because we're going to look at the situation where one, you do have to charge the same to everyone, and then we'll look at another situation known as price discrimination, where you don't have to charge the same to everyone. But let's just go with the model where you do have to change the same to everyone. So when you go from one room at 500 to two rooms at 400, your marginal revenue isn't the incremental 400, because this 500 is now 400 as well. So you go from 500 to 800, so your marginal revenue is an incremental 300, as you go from 500 total to 400 plus 400 or 800 total. And that's why, and we go into significant detail in other videos on this, and we do it with tables of numbers, and I encourage you to do that. That is why your marginal revenue curve for a monopoly has twice the slope, the negative slope, than your demand curve would have. So your marginal revenue curve would look something like this. And we've already talked about it in multiple videos, for any firm, it's rational to produce the quantity where marginal cost is equal to a marginal revenue. So this monopoly would produce this quantity, and the price they would get, well, that quantity, we go to look at the demand curve. The price would be right over there. So this monopoly firm would be able to get that price, and we can think about what its economic profit would be. On every room in this case, it charges that price. And its average total cost is this blue line right over here. So its average total cost are there, so the difference is how much economic profit per room, and then you multiply that times the total number of rooms, and so this area is the firms economic profit. Now, there is still some consumer surplus here. This is benefit that consumers are getting above and beyond what they're paying for it. So the consumer surplus in this situation would be all of this. So that first person who's willing to pay maybe $500 per room is now able to get this market price that everyone is able to get, which is maybe $300 per room, and so this benefit for that one unit, it goes to the consumer. And we've also seen that there is dead weight loss here. Your allocatively efficient when marginal cost is equal to the demand curve, and so, we study that in other videos. This right over here is our dead weight loss. But now let's imagine the other scenario. Let's say that we are a hotel, where we try to capture as much of someone's willingness to pay as possible. And I'll give a little bit of a idealistic scenario that doesn't really exist in the real world, but just to look at an extreme case. Let's say that you were able to get a computer that can read people's minds, and every time they call for a quote on a room, you know exactly what their willingness to pay is. So if I call, the computer says, hey, Sal's willingness to pay for that room is $375. So you quote me, all right $375, and I say, okay, sure. And then when that first person who has a high willingness to pay calls, it says, okay, why don't we quote them $500? And so we quote them $500, and so they get that room. And so in that situation, every incremental room, you don't have to change the prices on all the other ones causing this marginal revenue curve to slope down faster. Instead, every incremental room, you get those dollars. And so in that situation, your demand curve is equal to your marginal revenue curve. You're able to discriminate on prices. Let me write this. This is price discrimination. You're able to charge, and price discrimination is a general term for charging different customers, different consumers different rates, ideally based on their willingness to pay, and it might sound bad. In normal life, we don't like discriminating against others, but price discrimination is a very legitimate thing, and actually you will see it happen in things like the hotel industry, where they're going to try to charge different prices to different people based on their willingness to pay for essentially the same room. If you go stay in a hotel, it's very likely that the person in an identical room next to you is paying a different rate. Airlines will also do it. Now they're not going to be able to do it as perfectly as I just described with this magical computer, but they'll do it where, depending on how far ahead or whether you can return the ticket or cancel your reservation, you can get a different price, and the prices change over time. And so they're trying to capture as much of consumer's willingness to pay as possible. But if we took this extreme situation where you're able to charge exactly everyone their willingness to pay, well then, what is going to be the rational quantity for this profit maximizing monopoly to produce? Well, once again, it would be where marginal cost intersects marginal revenue, but the marginal revenue curve is now the demand curve. So it'd be right over there. That's the quantity that this monopoly would produce. And then, what's the price it would get? Pause this video and think about that. Well, you might be tempted to just go horizontally here and say, okay, this is the price it would get, like we did here. But remember, it's able to get a different price for every consumer. So there isn't just one price, like in this first example, that everyone is paying. So we can see the quantity it is producing. You can see the average total cost at that quantity, but the profit per room is going to be dependent on what people are willing to pay. This first person is going to pay a lot for it. They're not going to get any consumer surplus in this extreme example, and so all of this is going to accrue to the firm, and that's going to be the case for all of these consumers in this extreme circumstance. And so now, you have a fascinating situation. Notice, when this monopoly firm is able to do price discrimination, now, it's economic profit is far larger, economic profit. The consumer surplus shrunk through price discrimination. In the extreme example, it disappeared. But you also see that this is actually allocatively efficient. That we are actually producing at a quantity where marginal cost is equal to marginal revenue.