What is price discrimination? What are the conditions for price discrimination? How to distinguish different degrees of price discrimination?

Price discrimination is essentially a kind of price difference, which usually refers to the fact that when the provider of goods or services provides goods or services of the same grade and quality to different recipients, different sales prices or charging standards are implemented among the recipients. It is an act of price discrimination for an operator to impose different sales prices on several buyers of the same commodity or service without justifiable reasons. Price discrimination is an important monopoly pricing behavior and a pricing strategy for monopoly enterprises to obtain excess profits through differential prices.

Generally speaking, in a perfectly competitive market, all buyers pay the same price for similar products. If all consumers have enough knowledge, then the price difference between products of each fixed quality unit does not exist. Because any seller who tries to charge more than the current market price will find that no one will buy the product from them. However, price discrimination is very common in the market where the seller is a monopolist or oligarch.

Price discrimination: also known as price difference, refers to the behavior of manufacturers demanding different prices for the same product at the same time. Price discrimination can not only charge different prices for different buyers, but also charge different prices for different purchases of the same buyer.

There is a need.

1. Manufacturers must face a downward sloping demand curve, that is, products and their

Price discrimination

The price is inversely proportional.

2. Two or more purchasing groups must be able to distinguish a certain cost, which does not exceed the income that can be brought by distinguishing them. In other words, manufacturers can segment the market at a reasonable cost.

3. To prevent reselling between different buying groups.

4. The demand price elasticity of different buyers for products must be different, and manufacturers know it. That is, manufacturers understand the different demand levels of purchasing groups for products.

3 price discrimination

Direct differential pricing

Direct differential pricing means that manufacturers can determine consumers' different consumption preferences and thus determine prices. Suppose that the consumer market consists of four sub-markets A, B, C and D with the same scale. The consumers' willing prices in each sub-market are 40, 30, 20 and 10 respectively, and the unit production cost is 5, assuming that each consumer buys at most one unit product. If a single price is adopted, the optimal price must be one of 4O, 3O, 20, 10. When the price is 40, the sales volume is L and the profit is equal to 35 (40-5); When the price is 30, the sales volume is 2 and the profit is equal to 50 (30× 2-5× 2); When the price is 2O, the sales volume is 3 and the profit is 45 (20× 3-5× 3). When the price is 10, the sales volume is 4 and the profit is equal to 20 (10× 4-5× 4); So the optimal price is 30 and the maximum profit is 50. If differential pricing is adopted to make the price in each sub-market equal to the price that consumers are willing to make, the profit will be obviously improved, and the profit will be equal to 80 (40-50, 30-50, 20-50, 10-5).

Although direct differential pricing is the simplest method, there are often some problems in practice:

(l) It is difficult to determine the price of consumers' wishes;

(2) The market is difficult to subdivide;

(3) It is difficult to determine the price of a specific sub-market;

(4) There is no guarantee of resale between consumers;

5] Consumers may think that differential pricing is unfair;

[6] Market segmentation and pricing costs may be too high.

Therefore, in practice, the indirect differential pricing introduced below is more common.

Two-part pricing method

That is, the price consists of two parts, one is fixed price and the other is unit product price. This method can be regarded as a quantity discount because the average price of a unit product tends to decline with the increase of sales volume. Compared with single price, the existence of fixed price can make manufacturers get more consumer surplus, thus improving profits.

Figure L Suppose that Figure L represents a homogeneous market and consumers have the same demand curve. When a single price is adopted, according to the principle of profit maximization, the profit is the largest when the marginal profit equals the marginal cost. At this time, the price is P*, and the consumer surplus is F *；; When adopting two-part pricing, the fixed price can be set as Fc, and the unit price can be set as marginal cost C, so that the fixed price becomes the only profit source and the manufacturer gets all the consumer surplus.

Figure 2 So how do manufacturers use two-part pricing to realize the price difference? First of all, manufacturers can set the fixed price on the high side to exclude some consumers, because if these consumers buy, the fixed price will exceed their consumer surplus. Secondly, manufacturers can set different average prices for different consumers. As shown in Figure 2, if there are a large number of Class A consumers, the optimal pricing strategy is that the fixed price is the surplus of Class A consumers, and the unit price is higher than the marginal cost, so that both types of consumers will not be excluded, and the average price paid by Class B consumers is lower than that paid by Class A consumers.

Regional pricing

Regional pricing is the most common pricing strategy for quantity discount. There are at least two marginal prices, and the fixed price is dispensable. Figure 3 shows a three-region pricing strategy with no fixed price.

Fig. 3 When the purchase amount is less than or equal to Ql, the unit price is p1; When the purchase quantity is between Ql and Q2, the unit price of the part exceeding Ql is P2; When the purchase amount is greater than Q2, the unit price beyond Q2 is P3.

To illustrate the superiority of regional pricing, we can compare it with two-part pricing. Suppose (F 1, Pl) is the optimal two-part pricing shown in Figure 2. Consideration: the fixed price is still Fl. In addition, when the purchase quantity is less than or equal to Qb, the unit price is Pl, and the unit price above Qb is P2. In this way, the purchase amount of Class A consumers is still Qa, but the purchase amount of Class B consumers will increase from Qb to Qb'. Moreover, since P2 is greater than the cost C, the profit will also increase.

product line pricing

Manufacturers often introduce a variety of product lines and products to the market. Because the market competition is fierce, it is very important for manufacturers to occupy the shelves. A variety of products can make manufacturers occupy more shelf space, so product line management and pricing are very important for manufacturers. A product line consists of multiple products, and the difference between these products lies in the different attribute configurations.

Real estate regional pricing

And the basic functions are the same. For example, P&G light washing powder series has seven products, so a potential difficulty in product line pricing is the substitution between different products.

Fig. 4 in fig. 4(a), the willing price curves of two consumers intersect, so manufacturers can sell Y product to A with RyA and X product to B with Blg, and there will be no substitution phenomenon, because the price of X product is higher than A's willing price, and the price of Y product is higher than B's willing price.

In Figure 4(h), the two consumer willingness price curves do not intersect. If the price in (a) is still adopted, A will turn to X product, that is, X will replace Y, because when buying X product, A can get the consumer surplus of (Rxa— Rxb). The way to avoid this situation is to reduce the price of Y from Rya to below Rya-(RXA-RXB), so that A will get more consumer surplus when buying Y than X.

If the substitution problem is serious, that is, the price of Y needs to drop a lot, then we can consider deleting the substitution product, that is, reducing the length of the product line. For example, suppose that the number of consumers A and B is Na and Nb respectively, if Nb * RXB+Na (Rya-RXA+RXB).

Product set pricing

Manufacturers sometimes sell two or more products as a product set, which generally includes two situations: one is that the product set consists of different products, and the other is that the product set consists of the same products.

In the first case, the reason why manufacturers sell product collections is that if consumers' preferences for different products in product collections are negatively correlated, then selling products alone will either make the product pricing too low or exclude some consumers. The adoption of product set sales will neither reduce profits nor exclude consumers. Through product mix, manufacturers assimilate heterogeneous markets into homogeneous markets.

For example, if the manufacturer sells two products A and B, the consumer market consists of two sub-markets X and Y with the same size. Assuming that the unit cost of each product is less than 4, their willing prices are (12,4) and (4 12) respectively. If a single product is sold, the price of A is 12, the price of B is 4, X won't buy B, and Y won't buy A. However, if A and B are sold as a product set, the willing prices of X and Y for the product set are 16, so the sales will increase from 24 to 32, and no consumers will be excluded. However, this product set strategy also has a disadvantage, that is, the willing price of consumers may be lower than the marginal cost of products. For example, suppose the unit cost of the product in the above example is 6. If the product is sold separately, the profit is 12. When the product set is adopted, if the willing price of X to B and Y to A is less than the marginal cost, the profit will be reduced to 8. At this time, it is more favorable for manufacturers to sell separately.

In the second case, the manufacturer adopts product sets to increase sales. The most common examples are sports packages and concert packages. Take the annual sports package as an example, assuming that the number of annual competitions is n, the total cost is e, and the predetermined price is p, the manufacturer can know the number of consumers who are willing to buy the package at the price of p through sampling survey, and the number of attendees is (1.2.3 … n- 1.n), so as to get the total income, and then determine it according to the principle of profit maximization.

The above discussion is pure product set sales, but in fact, more mixed sales are adopted, that is, single product sales and product set sales are adopted at the same time.

In the marketing mix (product, price, location and promotion), promotion is the most commonly used and flexible. As a part of promotion, price promotion belongs to any form of price discrimination. Take commodity vouchers as an example. In 1980s, Schuster Department Store in Milwaukee, Wisconsin, USA began to issue coupons to customers. Today, there are about 250 commodity coupon companies in the United States. Sperry and Hutchinson Green Commodity Vouchers control 40% of the market. Only about 5% of the coupons of these companies have not been recovered. So, why do department stores issue coupons?

As we all know, the total price of a product should include not only the monetary price, but also the implied time opportunity cost. Here, time includes the time to find a product and buy it (and the time to consume it). We can assume that the more people pay attention to the time spent on free purchases, the less people are committed to finding low-cost purchase arrangements. In other words, a person whose estimated time is relatively higher than the monetary income will spend more money than the time spent in order to save the purchase time, and he will spend less time looking for a lower price. Therefore, in any given store, people with higher time estimates show more inflexible demand curves than those with lower time estimates. We assume that the time value has a strong correlation with a person's relative wealth, and the time value of richer people is higher than that of poorer people. Then, in a given store, a richer person's demand price elasticity will be lower than that of a poorer person. Retailers are faced with two types of consumers, one is relatively less elastic and the other is relatively more elastic. The problem for retailers is to distinguish between two types of consumers and charge higher prices to richer consumers. A method

Price discrimination

It is to provide rebates to customers who are willing to spend time and cost. The rebate is in the form of commodity coupons. Therefore, people who want kickbacks must collect and keep commodity coupons, and then exchange them at designated places. All these activities need time, so that poorer people with greater demand elasticity will pay lower prices for the goods they buy, because they can get the goods when they redeem coupons. However, wealthy consumers with less elasticity of demand will reject these coupons because of the time cost. They don't enjoy any kickbacks when shopping.

Price discrimination can be divided into first-class price discrimination, second degree price discrimination and third-class price discrimination.

(1) If the manufacturer sells each unit of product at the highest price that consumers are willing to pay, this is first-class price discrimination; First-class price discrimination is also called complete price discrimination.

(2) Asking different prices only for different consumption quantity segments is called second-degree price discrimination; There is no serious price discrimination in second degree price discrimination.

(3) Monopoly manufacturers charge different prices for the same product in different markets (or for different consumer groups), which is called three-level price discrimination.

4 Three grades

According to the degree of price difference, price discrimination can be divided into three levels:

First-class price discrimination

Also known as complete price discrimination, that is, each unit product has a different price, that is, it is assumed that the monopolist knows the maximum amount of money that each consumer has to pay for any quantity of products, and determines its price accordingly, and the determined price is exactly equal to the demand price for products, thus obtaining all the consumption surplus of each consumer. This is an extreme situation, which rarely happens in reality.

second degree price discrimination

That is, the monopolist understands the consumer's demand curve, divides this demand curve into different segments, and determines different prices according to different purchase quantities, so that the monopolist can obtain part but not all of the buyer's consumption surplus. The differential price of public utilities is typical of second degree price discrimination.

third degree price discrimination

It means that monopoly manufacturers impose different prices on different consumers in different markets.

First-class price discrimination

Earn excess profits in a high-priced market. Because we can make full use of our own equipment resources, it is of positive significance to adjust some peak demand to low peak period by using peak-valley differential electricity price.

In China, price discrimination needs to be seriously discussed and regulated according to different situations. Paragraph 5 of Article 14 of the Price Law stipulates that an operator shall not discriminate against other operators with the same conditions when providing the same goods or services. The "price discrimination" mentioned here means that the providers of goods or services provide the same level and quality.

Goods or services make the recipients of the same trading conditions in an unequal position in price. For example, business operators treat different buyers of the same commodity or service with the same conditions without justifiable reasons.

For enterprises of Party A and Party B with the same conditions, Party A can implement batch pricing, while Party B is not allowed to do so; Or you can bargain with A, but not with B; Or because A is a local enterprise and B is a foreign enterprise.

Implement different price treatments, etc. , which constitutes price discrimination. Price discrimination puts several buyers with the same conditions in an unfair position, hinders their legitimate competition and has the harm of restricting competition. Therefore, the anti-monopoly laws and regulations of all countries in the world basically restrict it.

In a perfectly competitive market, all buyers pay the same price for homogeneous products.

5 Monopoly

Monopolists take advantage of price discrimination to make profits.

Discrimination means different treatment. Take price discrimination as an example, that is, the same product is sold to different people and charged different prices, which forms price discrimination. However, by extension, there are many forms of discrimination, which give different treatment to different people in the same living range.

Different people not only have different economic characteristics, but also have different national characteristics, gender characteristics or regional characteristics. Different treatment can be different price treatment, different employment treatment or different reputation treatment. In this way, in addition to price discrimination, racial discrimination, gender discrimination and geographical discrimination will also occur accordingly. But the most common thing in life should be price discrimination. Economic analysis shows that once the sellers of products form monopoly, it is very easy to form price discrimination. There are usually three forms of price discrimination: first-class price discrimination, second degree price discrimination and third-class price discrimination.

First-class price discrimination: When the seller has strong monopoly power and well-informed information, the seller can charge the highest price that the buyer is willing to pay for each unit of goods, and the rest of the consumers keep it for themselves. Suppose there is only one dentist in a certain area, and he knows the highest price that each patient is willing to pay. He will charge different prices for each patient, so that they are only willing to treat, so that all the rest of the patients' consumption will be transferred to the dentist.

Second-degree price discrimination: Monopoly sellers can also charge different prices according to the quantity purchased by buyers. For example, telecom companies charge different prices for customers' different monthly online time, and charge higher prices for customers with small usage; For customers who use a lot, charge a lower price. In this way, the monopoly seller takes part of the buyer's consumer surplus as his own.

Three-level price discrimination: monopoly sellers charge different prices to different types of buyers, and the greater the price elasticity of buyers' demand, the lower the price charged by sellers; The smaller the buyer's demand price elasticity, the higher the price charged by the seller. In this way, the monopoly seller squeezed more consumer surplus from the buyer with low elasticity of demand price. For example, some tourist attractions discriminate against foreign tourists and local tourists in price, charging higher prices for foreign tourists and lower prices for local tourists.

Obviously, price discrimination is beneficial to the seller of the product as much as possible, because through price discrimination, the consumer surplus originally belonging to the buyer of the product is also transferred to the seller. However, according to the analysis of economists, price discrimination is economic and effective, that is to say, price discrimination meets the Pareto standard. Through price discrimination, the seller's maximum income is equal to the maximum value of social welfare. If the monopoly seller implements a unified price, although it can maximize profits, it is less than the maximum value of social welfare, so it is economically inefficient.

Of course, in order for price discrimination to work, monopoly sellers must be able to effectively distinguish and divide the different characteristics of buyers. This difference may be the difference of buyer's demand intensity, the difference of purchase quantity, and the elasticity of demand price.

Different, the key is to effectively distinguish and divide this difference. For example, airlines often fight price wars, and preferential prices can often be discounted very low. However, even if it is a price war, airlines are not willing.

The intention is that business travelers will get lower prices from the price war. However, when a passenger buys a plane ticket, there is no sign on his face, indicating whether he is traveling on business or privately. So how can airlines distinguish passengers and divide the market?

What about the venue? It turns out that there are always some conditions for buying discounted air tickets, such as booking tickets two weeks ago and spending one or even two weekends at the destination. When the boss sends you on a business trip, you are often in a hurry and seldom in.

A domestic trip planned two weeks ago. This makes it impossible for some business travelers to get preferential air tickets.

Best of all, you must spend the weekend at your destination. The boss sent you on a business trip, of course, to let you stay in a better hotel and give you a poor allowance. spend time

Stay at least two more days on weekends, and two weekends are even worse. This expenditure is definitely much more than the money that can be saved by enjoying preferential fares. What's more, you won't come back until after the weekend, and you will lose several days in the company's working day.

A shrewd boss won't be greedy for petty advantages and suffer big losses for that immediate discount. In this way, everyone is equal before the conditions, and these preferential conditions exclude people who are on business trips.

This satisfies the discriminators: it not only taps the potential demand, but also excludes those who should not enjoy this preferential treatment from the perspective of the discriminators. From this point of view, the implementation of price discrimination by airlines is completely successful.

6 specifications

Differential prices, competition laws in the United States and other western countries all involve price discrimination. American anti

The trust legal system has always studied and regulated some price discrimination that harms market competition as a typical unfair competition behavior. Engage in commercial activities according to the provisions of Clayton Act and Robinson patman Act.

In the course of business, 70% people directly or indirectly discriminate against buyers of goods of the same grade and quality, if the result of price discrimination substantially reduces competition or aims to form a monopoly on business or cause other competition.

Damage is illegal. The constitutive requirements of illegal acts of price discrimination are as follows: the main body of price discrimination includes sellers and buyers of goods; The subject matter of price discrimination is only goods, excluding services and intangible things, and this kind of goods

Must have the same grade and quality, and the sale of goods takes place in the business process of the United States; The consequences of price discrimination are not conducive to market competition.

The embodiment of price discrimination in real economic life

The implementation of price discrimination is closely related to information. The first-level price discrimination needs the most information, followed by the third-level price discrimination, and second degree price discrimination needs the least information. In real life, first-class price discrimination is unlikely to happen, while third-class price discrimination and second degree price discrimination are very common.

Price discrimination in telecommunications industry

There is widespread price discrimination in telecom pricing practice, which is embodied in various tariff choices that customers face when purchasing their products or services. In fact, the pricing mode of tariff selection is composed of several two-part tariff pricing schemes, and the two-part tariff can further include time-sharing tariff or split-journey tariff. The so-called two-part fee means that the price plan consists of two parts. One is the basic fee that has nothing to do with the communication time of telecom users, such as "monthly fee"; The second is the specific fee paid according to the communication time. The law of daily work and life determines people's different needs for communication services in different time periods. By setting different tariff standards in different time periods, manufacturers achieve the purpose of three-level price discrimination. Furthermore, by setting selective tariffs with multiple two-part pricing, manufacturers can obtain lower marginal prices (quantity fees) and higher basic fees from high demanders, and higher marginal prices and lower basic fees from low demanders, thus achieving the purpose of second-degree price discrimination. It can be seen that through the combination of time-sharing pricing and two-part pricing, telecom manufacturers actually implement three-level and second degree price discrimination for users at the same time.

Second, the embodiment of price discrimination in e-commerce

Compared with the physical market, price discrimination in e-commerce market has different characteristics in form and application. Its specific manifestations are: first, personalized pricing, corresponding to the first-level price discrimination in the physical market, that is, selling to each user at different prices, the seller can get all the detailed information of the user; The second is version division, which corresponds to the second price discrimination in the physical market, that is, providing a product series for users to choose the version that suits them; The third is group pricing, which corresponds to the three-level price discrimination in the physical market, that is, setting different prices for different consumer groups. The external effect of the network, the locking effect of digital products and the * * * enjoyment effect make it more advantageous to implement three-level price discrimination in the e-commerce market.

Third, price discrimination in the civil aviation industry

By strictly applying some restrictions, airlines divide passengers with different willingness to pay into different groups, thus achieving the purpose of three-level price discrimination. On the basis of the above classification, according to the different levels of services provided, second degree price discrimination is implemented for consumers in the quality dimension. The main measures to implement price discrimination in civil aviation industry are as follows: (1) setting pre-purchase or minimum stay period for low-cost air tickets, stipulating that they cannot be refunded or fully refunded; For direct flights, stop flights and transit flights, discounts will be implemented at some specific times; Take full-price tickets to attract passengers to buy economy class, such as providing first class and business class services and providing extra services to full-price passengers in economy class. Through the above methods, airlines can more clearly divide the passengers in the market into different groups, so that the differences between groups are more obvious, thus implementing more effective price discrimination for basically the same services in different markets.

7 facing difficulties

In addition to the fairness problem caused by different prices of similar goods to different consumers, price discrimination actually redistributes part or all of consumers' income to producers, and the increase of producers' profits is at the expense of consumers' interests. In addition to the price discrimination in the final product or service market, there is often price discrimination in the intermediate product market, which will directly lead to unfair competition among downstream enterprises. Out of respect for consumers' rights

Protection of interests and obvious price discrimination prohibited by anti-monopoly laws or restrictive competition laws in various countries. China's Price Law clearly stipulates that price discrimination is an unfair price behavior.

And stipulated more severe punishment measures. Although price discrimination is quite common in real economic life, it is rare to bring manufacturers to court because of price discrimination. The main reasons are as follows.

Key points:

1. Difficulties in defining price discrimination

From the definition of price discrimination, it can be seen that if producers are based on production costs

Different prices charge corresponding fees, and this form of differential pricing cannot be called price discrimination. If the producer charges the same price for the same commodity with different production costs, strictly speaking, the producer is also implementing the price at this time.

Discrimination, so that the definition of price discrimination will be too broad. On the other hand, if goods delivered at different times, places and conditions or goods with different quality are regarded as different economic goods, then

The scope of "pure" price discrimination may be very limited, which will make the definition of price discrimination too narrow. If the price difference between consumers only reflects the production cost difference of manufacturers, it can be considered that there is no price discrimination, but just as only consumers know their own preferences and needs, in reality only manufacturers know the cost difference of products or services they provide, and there is cost information asymmetry between regulators and regulated manufacturers, which greatly increases the difficulty for regulators to define price discrimination. It is precisely because of the above reasons that although there are a lot of price discrimination in real life, few of them are really defined as price discrimination and restricted by the regulatory authorities.

Second, the welfare result of price discrimination is uncertain.

Because the first-level price discrimination is rare in real economic life, this paper only analyzes the welfare of second degree price discrimination and the third-level price discrimination. Compared with unified pricing, the welfare analysis results of second degree price discrimination and three-level price discrimination are uncertain. Although forcing monopolists to set uniform prices can reduce the profits of monopolists, consumers may not benefit from it. This is especially dangerous when the control of price discrimination leads to the closure of some markets. Therefore, in the absence of price discrimination, the corresponding products can not be supplied by manufacturers, price discrimination is beneficial to both producers and consumers, and will eventually enhance social welfare. It can be seen that although there are a lot of second degree price discrimination and tertiary price discrimination in real life, due to the uncertainty of its welfare results, the regulatory authorities are in a dilemma in regulating price discrimination.

Three-dimensional price discrimination

In addition to price discrimination in quantity, manufacturers can also implement price discrimination in other dimensions such as quality. Defining price discrimination in the quantitative dimension is relatively tolerant.

If it is easy, it is much more difficult to define price discrimination in other dimensions such as quality, mainly because the price discrimination in the quantitative dimension is more intuitive and easier to measure, and as a branch, there are a lot of theoretical research results.

Hold on. In sharp contrast, the price discrimination in the quality dimension is not only difficult to measure, but also has the problem of asymmetric cost information of manufacturers. In some cases, consumers choose both quantity variables and quality variables, so monopolists can discriminate against prices in both quantity and quality dimensions. The lack of theoretical research results and the confusion of asymmetric information make it impossible for the regulatory authorities to regulate price discrimination beyond the quantitative dimension.

Fourth, the lack of laws and regulations.

At present, more and more multinational companies have settled in China, and it is very common for multinational companies to implement price discrimination in sub-markets of different countries. Despite China's ban

Laws and regulations to stop price discrimination, but their scope of application is limited to China, and there are no relevant provisions in international law to restrict transnational price discrimination. Therefore, under the framework of the current legal system, it is necessary to treat multinational companies differently.

In fact, the regulation of price discrimination between national markets is in a state without legal basis.

8 application method

[1]( 1) coupon: consumer screening

Manufacturers often distribute coupons for their products or services through newspapers, magazines and other channels. Consumers who hold coupons enjoy certain discounts when spending than those who don't, which is more attractive to low-income groups. Through coupon discount, consumers with high elasticity of demand price pay lower prices, while consumers with low elasticity pay higher prices. Here, manufacturers distinguish between high-income and low-income customers and let customers choose for themselves, which greatly reduces the information requirements of price discrimination.

(2) Double accusation

Double charging refers to the behavior that monopoly manufacturers ask consumers to pay first to get the right to buy a commodity, and then consumers pay extra for each unit of commodity they want to consume, that is, they charge entrance fees and use fees successively. For example, the telephone service fees charged by telecom companies include telephone installation fees and monthly fees. When monopoly manufacturers face many consumers with different demand levels,

There is no simple formula to calculate the best double charge standard. But there will always be some alternatives: lower admission fees mean more entrants and more sales profits; But with the registration fee,

With the decrease of entrants and the increase of entrants, the profit brought by the entry fee will decrease, so the problem lies in choosing an entry fee that can lead to the best number of entrants and thus generate the maximum profit.

(3) Bundle sales

Bundle sales refers to the fact that manufacturers require customers to buy one of their products at the same time, they must also buy another product. There are some differences in customers' preferences, but manufacturers can't.

Under the condition of price discrimination, this strategy can improve the profits of manufacturers. When the demand is negatively correlated, bundled sales are more profitable than individual sales; When the demand is positively related, bundling does not necessarily bring additional costs to manufacturers.

Income.