KR20040025262A - Method of Selling Goods Online - Google Patents

Abstract

PURPOSE: A method for selling goods on the online is provided to induce more interests by applying a discount rate differed from each buyer, and to remarkably reduce a risk for the credit information leakage by shortening a state that a settlement tool is opened. CONSTITUTION: The information of a discounted price different with each other is written to a part of a buying order for the selling goods. A buying request of the buyer is received from a buyer terminal. The settlement tool selected by the buyer and the settlement information are received. A plurality of media selected by the buyer is offered to the buyer(S182). If the buyer selects one media, the discounted price corresponding to the buying order is displayed(S187). The discounted price and the settlement information are transmitted to a settlement organization server, and are settled by the settlement tool. The settlement completion information is received from the settlement organization server.

Description

How to sell your goods online {Method of Selling Goods Online}

The present invention relates to a method for purchasing a product online, and in particular, to selling a product at a discounted price to a buyer.

The business of selling goods online is exploding due to the spread of the Internet. The seller does not have to store a separate store to display and display the product, and the buyer can check the appearance and performance of the product through the monitor even if the product does not stop by the store and examine the product. You can easily get information about the product by reading the period of use, etc., has the advantage of saving time.

In addition to these online sales, there is also a so-called home shopping that can introduce products through television and sell / buy products through telephone orders.

The advantage of home shopping is that you can observe the operation of the product or the appearance of the product from various angles. In recent years, online merchandise is also included to provide a video, including the advantages of the home shopping.

Since the online shopping company can reduce the logistics cost and the like, it is possible to discount the price compared to the products on the offline. By lowering the price of the product as described above there is an effect that can increase the sales volume of the product. In the conventional online shopping, the discounted price of the product is applied to all the buyers at a discount rate determined by the operator when discounting the product.

In addition, for a buyer who has applied for the sale of online goods within a predetermined period of time, they receive a certain participation fee, and after this period, the discount amount is applied only to the buyers who have won the lottery and the remaining buyers. For these products, a method of selling an online product is known, which allows purchase at an undiscounted market price. However, at this time, the payment means must be open until the predetermined period has elapsed from the time when the buyer applies for a purchase (if the payment information is input and only the amount is settled), the credit card is the only payment method. As long as the credit card is open for a long time, the risk of credit information leakage increases, and the inconvenience of the buyer is caused by applying, paying and receiving the product for a period of time.

An object of the present invention is to solve the above-mentioned problem in a method of selling goods online.

1 is a system configuration for performing a product selling method according to the present invention.

2 is a flowchart of a product selling method according to the present invention;

3 is a flowchart of a method for determining a discounted amount in a product selling method according to the present invention.

Figure 4 is a flow chart of the purchase amount confirmation and payment step in the product sales method according to the present invention.

FIG. 5 shows an example of a merchandise database of the system shown in FIG. 1; FIG.

6 shows an example of a member database of the system shown in FIG.

7 shows an example of a discount policy database of the system shown in FIG.

FIG. 8 is a diagram showing an example of an allocation database for each winning card of the system shown in FIG. 1; FIG.

9 shows an example of a sales information database of the system shown in FIG.

10 illustrates an example of a winning discount amount database of the system shown in FIG.

Fig. 11 is an example of an initial screen when a site is connected to a product selling method according to the present invention.

FIG. 12 is an example of a screen displaying brief information on products included in a product group when a product group is selected on the initial screen of FIG.

FIG. 13 is an example of a screen displaying detailed information of a product when a product is selected on the screen shown in FIG. 12; FIG.

14 is an example of a screen displaying a corresponding input field so that a registered member can input a member ID and password.

Fig. 15 is an example of a screen displaying a required input field for a user who is not registered to access and register as a member.

FIG. 16 shows an example of a screen for inputting payment and delivery information of a product when a user selects a product purchase for a predetermined product. FIG.

FIG. 17 is an example of a screen for inputting card information when a user selects a credit card payment on the screen shown in FIG. 16; FIG.

18 is an example of a screen for displaying information such as the original price and quantity of a product after the selection of a payment method is completed and confirming that the process can proceed to a discount amount determination step.

19 is an example of a screen displaying a card selection game which is an example of a discount amount determining step.

20 is an example of a screen displaying a discounted amount on a card selected by the user when the user selects a predetermined card on the screen shown in FIG. 19;

FIG. 21 is an example of a screen displaying final payment amount and purchase information after a discount amount is determined in FIG. 20; FIG.

22 is an example of a screen in which a system operator according to the present invention can enter and register a discount policy.

23 is a flowchart for generating a winning discount amount database based on the probability of determination.

24 is a flowchart of the regeneration phase of the winning discount amount database.

<Explanation of symbols for the main parts of the drawings>

1: main server

2: communication equipment

3: communication network

4: client system

5: payment agency

6, 7: user terminal

According to a first aspect of the present invention, there is provided a method for selling goods online, comprising: a main server, a purchaser terminal connected to the main server through a communication network, and a main network connected to the main server. An online product selling method performed in an environment including a payment institution server, the method comprising: recording information of different discounted amounts for at least some of the purchase order numbers for the product to be sold; Receiving from the buyer terminal, receiving payment information other than the payment method and payment amount selected by the buyer, providing the buyer with a plurality of selected media to be selected by the buyer, and If the selected medium is selected, the purchase order of the buyer Displaying the discounted amount, transmitting the discounted amount and the payment information to the payment institution server for payment by the payment means, and receiving payment completion information from the payment institution server. .

In the method for selling goods online on the second aspect of the present invention, in the method of the first aspect, the purchase order number is a predetermined number, and if the predetermined number order is exhausted, the order number is sequentially. Increasing the rate and rewriting each different discounted amount for at least some of the increased turn.

According to a third aspect of the present invention, there is provided a method of selling goods online, wherein in the method of the first or second aspect, a buyer can select a plurality of the selected media, and the buyer can select a plurality of the selected media. If it is selected, and further comprising displaying the discount amount allocated to the purchase order of the buyer through any one of the selected medium.

The method of selling goods online in accordance with the fourth aspect of the present invention further includes the step of recording the information of the buyer when the purchaser receives a discount amount in the first or second aspect. .

According to a fifth aspect of the present invention, there is provided a method for selling goods online, in the first or second aspect, when the payment completion information is received from the payment institution server, the information of the buyer, the product information purchased by the buyer, and the payment. And recording the amount of money information.

A method for selling goods online in accordance with the sixth aspect of the present invention includes a main server, a purchaser terminal connected to the main server through a communication network, and a payment institution server connected through the main server and a communication network. In the online merchandise sales method performed in an environment, recording information of different discounted amounts for at least some of the purchase order numbers for a product to be sold, and receiving a purchase request of a buyer from the buyer terminal. And receiving the payment method and payment information selected by the buyer, and transmitting the received payment method and payment information to the payment institution server, providing a plurality of selected media that the buyer can select, and allowing the buyer to select the selected media. If selected, the discount amount corresponding to the purchase order of the buyer Displaying and refunding the purchaser an amount corresponding to the discounted amount.

The merchandise selling method according to the seventh aspect of the present invention is performed in an environment including a main server, a purchaser terminal connected to the main server through a communication network, and a payment institution server connected through the main server to a communication network. A method of selling goods online, the method comprising: receiving a purchase request of a buyer from the buyer terminal, receiving payment information other than the payment method and payment amount selected by the buyer, and selecting a plurality of selected items by the buyer Providing a medium for the buyer to select, determining a discount amount based on a probability of change when the buyer selects the selected medium, and displaying the discount amount applied to the buyer, the discount amount and the settlement Payment by the payment means by sending information to the payment authority server And receiving payment completion information from the payment institution server.

According to the merchandise selling method, when the buyer selects the medium to be selected based on the probability of variation rather than the predetermined probability, the discount amount that the buyer can apply is determined and displayed.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the present invention.

1. System Environment

1 shows a system environment for carrying out a method of selling goods online according to the present invention.

As shown in Fig. 1, the system for performing the merchandise selling method according to the present invention includes a client system 4 for recording information and registering the merchandise with the main server 1, and on-line according to the present invention. A main server (1) for selling goods in a merchandise selling method, and communication equipment (2) for communicating with users or buyers.

The main server 1 includes a merchandise database 11, a member database 12, a discount policy database 13, an allocation database 14 for winning cards, a sales database 15, The winning discount amount database 16 is connected. The main server 1 is connected to the communication network 3 via the communication equipment 2. The communication equipment 2 may be an ARS device. The purchaser connects to the communication network 3 using the personal computer 6 or the information communication device 7 to search for the goods registered in the main server 1 or to purchase the goods. The information communication device 7 is a wireless or wired device and includes, for example, a cellular phone and a PCS phone or a PDA.

The client system 4 connected to the main server 1 is connected with a scanner (not shown) or a barcode reader (not shown) to read a product image and register it with the main server 1, or the administrator Various information necessary for selling goods online such as price and discount amount can be recorded in the main server 1 and the databases connected to the main server 1.

2. Database

(1) product database

As shown in FIG. 5, the product database 11 includes a product code (PDC), a product name (PDN), a product standard (STN), a market price amount (PRC), a supplier code (SPC), and a registration date (RGD). Etc. are recorded linked to each other. When a product is registered in the main server 1 through the client system 4, the main server 1 stores the above information about the product in the product database 11, and stores the existing data each time new data is upgraded. Update

(2) Member Database

As shown in Fig. 6, the member database 12 includes a member's ID, a password for the member to log in (PWD), a member's name (NME), and a postal code (ZCD) of the member's address. , The address (ADR), the member's telephone number (TPN), the e-mail address (EMA), the credit card name (CDM) the member has registered to use for the purchase of the product, and The card number CDN, the card password C_PWD, and the validity period EPD of the card are recorded.

(3) discount policy database

The discount policy database 13 records information necessary for an administrator to determine a discount amount for each product in the online product sales method according to the present invention. As shown in FIG. 7, the discount policy database 13 includes a product code (PDC), a display card number CN for allowing a buyer to select from among them, a winning card number WCN, and a number for the buyer. The number of selectable cards (SCN) from among the display cards, the total discount amount (TD) set as the total discount amount for the product corresponding to the product code (PDC), and the number of the first purchase order set for the product. The total turnover (TSN), the winning turnover (WSN), which is the number of winning turn numbers to which a discount amount is applied among the number of purchase turnovers, the current turnover (CSN) that the buyer proceeds to purchase, and the total turnover (TSN) ) Is exhausted (ISN), the number of newly created purchase numbers, and IWSN, which is the number of winning numbers to which a discount amount is applied among the purchase numbers increased by the increase times, are recorded.

The number of winning cards WCN means, for example, the number of cards in which the discounted amount is displayed among the cards displayed on the screen of the purchaser's terminal 6 to the information communication device 7. For example, if the display card number CN is set to "10" and the winning card number WCN is set to "3", a total of 10 screens of the purchaser terminal 6 to the information communication device 7 are displayed. The card is displayed, indicating that the discount amount is displayed on three of the cards.

When the buyer selects more than the number set in the selectable card number SCN, the main server 1 displays an error message and allows the buyer to select the card again.

The total discount amount (TD) refers to the total amount that the operator wants to discount per purchase of the unit total turnover (TSN) for the product. For example, in the case of selling 10 refrigerators with a list price of 1 million won, if the total amount to be discounted is set to 2 million won, 2 million won is recorded in the total discounted price (TD).

By adjusting the WSN, you can give a discount to every buyer who buys a prize, or you can give a discount to only a few and make sure that the rest of the buyer pays the full price to purchase the prize.

22 shows an example of a registration screen of the discount policy database 13. The manager or the service provider inputs data necessary for the discount policy as described above through the screen shown in FIG. 22 through the client system 4.

(4) Assignment database by winning card

Information on the discount amount set for each product is recorded in the allocation database 14 for each winning card. As shown in FIG. 8, a product code (PDC) and the number of cards corresponding to the product (NOC) The discount rate DR, the discount amount DP, and the quantity AMT to which the discount rate and the discount amount are applied are recorded.

On the basis of the information recorded in the above-described discount policy database 13 and the winning card-specific allocation database 14, data of the winning discount amount database 16 described later is generated and recorded.

(5) sales database

In the sales database 15, information on purchases of a member is recorded for each member. As shown in FIG. 9, a member ID, a product code (PDC), a product name (PDN), and a sales date ( SDT), the supplier code (SPC) of the product, the amount SP paid by the member to purchase the product, and the like are recorded.

(6) Discount Amount Database

A prize code PDC, a turnover PO, a discount amount DP, and a winner ID are recorded in the discount amount database 16 for the winning.

Next, a process of generating a winning discount amount database 16 for each prize will be described with reference to FIG. 23.

First, the number of records corresponding to the total turnover (TSN) set for each product is generated in the temporary file A with reference to the discount policy database 13 (S20). Then, the record is recorded in the discount policy database 13. As many times as the number of records set in the WSN is extracted from the temporary file A with reference to the WSN, the lower limit is " 1 " and the upper limit is a random number. Record as many times as the winning prize (WSN) and store it in the temporary file B (S21).

Next, the discounted amount DP and the quantity AMT recorded in the allocation database 14 for each winning card are read. (S22) The highest discounted amount is the upper limit and the lowest is the upper limit of the read discounted amount DP. Using the discounted amount as a lower limit, a random number is generated based on the discounted quantity (AMT) and sequentially assigned to the record stored in the temporary file B (S23).

Through the above-described steps, a record of the temporary file B, to which the discount amount DP is allocated for each winning time, is recorded in the discount amount database 16 for winning. (S24) When the recording ends, the temporary file A and the temporary file are temporarily recorded. The data stored in the file B is deleted (S25), and the generation step of the winning discount database 16 ends.

As described above, when a purchase is made for the total number of TSNs that are initially set, the number of new purchase sequences, that is, the times, must be increased, and the discounted amount database 16 for the winnings is required for the increased times. Therefore, if the number of times increases as described above, the winning discount amount database 16 must be regenerated.

Hereinafter, the step of regenerating the winning discount amount database 16 will be described with reference to FIG. 24.

First, by checking the winning discount amount database 16 (S30), and checking whether the winning discount amount database data is the last or the reference value set in the system (S31), and determines this (S32), If the winning discount amount database 16 is the end of the data or the reference value set by the system is reached, the values of the incremental turnover (ISN) and the incremental drawback turnover (IWSN) of the discount policy database 13 are read. S33)

In the next step, the winning discount amount database 16 as shown in FIG. 23 is formed to generate data in the winning discount amount database 16 (S34) and the discount policy database. In the total turn TSN (13), the increased turn ISN is accumulated (S35), and the regeneration step of the winning discount amount database 16 is ended.

3. Product Purchase Step

The purchaser connects to the main server 1 via the communication network 3 using the personal computer 6 or the information communication device 7 or the like (S1). Hereinafter, the case where the communication network 3 is the Internet will be described.

FIG. 11 illustrates an example of an initial shopping mall screen displayed in a web browser when a buyer accesses the main server 1 through the Internet. FIG. 2A illustrates a present invention in which a buyer accesses an internet shopping mall as shown in FIG. The flow of purchasing according to the purchase method is shown.

In the initial screen illustrated in FIG. 11, product groups are displayed by type, and the latest hit products and newly released new products items may also be displayed to help the purchaser. As shown in FIG. 11, product groups may also be displayed in the hit product and the new product item.

When the buyer selects a product group to purchase or search on the initial screen as shown in FIG. 11, brief information of the products included in each product group is displayed on the buyer's web browser as shown in FIG. 12. The brief information includes a product number assigned to each product, a manufacturer or supplier, a consumer price, and an average discount rate. Average discount rate means the expected value of the average discount rate that can be applied when purchasing the product. The product number may be a product code (PDC) recorded in the above-described discount policy database 13, and the consumer price means the market price of the product before the discount rate is applied.

When the purchaser clicks on the "more details" item and selects a product to be purchased (S2), more detailed information about the product and a screen for starting the purchase of the product are displayed on the buyer's web browser. As shown in FIG. 13, the detailed information may include the performance of the product, the contents of the design, the contents of the color, the size, the capacity, and the like. The information on the purchase of the product may include a discount price set for the product, a quantity that can be applied to each of the discount prices, a probability of winning the discount price, and the like.

In addition, the above screen may be displayed to guide the purchase method for buyers who are new to the sale of online products according to the present invention.

When the buyer clicks on the "buy" item and confirms the purchase of the product (S3), a screen as shown in FIG. 14 is displayed. The above screen can be used to enter the member ID and password registered on the site that performs the online product sales according to the present invention, start the membership registration or click on the "non-member purchase" item for the buyer without a member ID So that you can purchase as a non-member. The buyer selects a member purchase or a non-member purchase on the screen shown in FIG. 14, and selects a product purchase method (S4). When selecting a member purchase, the purchaser receives a member ID and a password to check whether the member is registered. (S6).

When it is confirmed that the registered member is registered, the member information and the delivery address information are displayed through the screen as shown in FIG. 16A with reference to the data recorded in the member database 12 for the member (S10). In the screen shown in FIG. 16A, the name of the product selected by the buyer, the price of the product, and the quantity of the product selected to be purchased are also displayed. The payment method selection item for selecting a payment method is also shown in FIG. 16A. It is preferred to be displayed as indicated.

On the other hand, if the buyer is a non-member and wants to purchase as a non-member, the process proceeds to step S7 to receive the corresponding buyer information and delivery address information. If the purchaser wants to purchase after registering as a non-member, proceed to step S9 to receive information necessary for membership registration. An example of a screen for receiving information required for member registration is shown in FIG. 15. When member registration ends, the process proceeds to step S10 to display the registered member information and the delivery address information.

If the buyer wants to change the delivery address (S11), the changed delivery address information is recorded in the member database 12. If it is desired to deliver to the delivery address previously recorded in the member database 12 without changing the delivery address information, the flow proceeds to step S13. In step S13, the buyer selects a payment method. When a payment method is selected on the screen as shown in FIGS. 16A to 16B and clicks "OK", the process proceeds to step S14 to receive input of payment information required for payment with the selected payment method. 17 illustrates an example of a screen for receiving payment information when the buyer selects a credit card payment. The payment information received on the screen shown in FIG. 17 includes a card number, an expiration date, a resident registration number and a card password, and the resident registration number and card password can be omitted. At this time, the payment amount is determined through a process as described below, and since it is not yet confirmed, do not receive an input.

In this way, the payment information received from the buyer is sent to the payment institution undergoes an inquiry process (S15), and if the payment result is a payment method (S16), the received payment information is stored in the member database 12 (S17). .

Next, the process proceeds to step S18 to determine the product discount amount. In the present embodiment, the discount amount is determined by the card selection, an example of the start screen of the product discount amount determination step is shown in FIG. Clicking "OK" on the screen shown in FIG. 18 displays a card selection screen as shown in FIG. Preferably, the screen displays contents indicating the number of cards that the buyer can select. 20 illustrates an example of a screen in which the discounted amount is displayed on the cards in which the discounted amount is determined in advance, including the card selected by the buyer. In the screen shown in FIG. 20, the amount of payment that the buyer actually pays in order to purchase a product is finally determined (S19), and when the user clicks "OK" on the confirmation screen as shown in FIG. 21, the payment is already selected. The actual purchase amount is settled by subtracting the discounted amount from the market price amount by the means (S20).

3 is a detailed flowchart of a determining step of determining a discount amount in the online product selling method according to the present invention.

When the buyer starts the discount amount determination step by clicking " OK " on the screen as shown in FIG. 18, the product code (PDC) recorded in the product database 11 and the discount policy database corresponding to the code With reference to the number of cards CN to be recorded recorded in (13), the number of cards is displayed on the screen (S182).

The buyer selects the number of cards that are to be selected according to the instructions on the screen (S183). The number of cards to be selected is determined with reference to the number of selectable cards SCN recorded in the discount policy database 13. Next, the process proceeds to step S184 to determine whether the number of cards selected by the buyer is the number of selectable cards (SCN), and if there is no match, returns to step S183 to select the cards again and matches If yes, the flow proceeds to step S185.

In step S185, the current turn (CSN) recorded in the discount policy database 13 is checked to confirm the purchase order number, and the record recorded in the winning discount amount database is read. Check whether the corresponding record is recorded in the winning discount amount database 16 (S186), and if there is a corresponding record in the winning discount amount database 16, the process proceeds to step S187, and the record is If not, the process proceeds to step S189 and accumulates the value of the current turn CSN of the discount policy database by 1 and ends. In step S187, the discounted amount recorded in the corresponding round of the winning discounted amount database is displayed on the screen. Next, the buyer's ID is recorded as the winner ID in the corresponding round record of the winning discount amount database (step S188), and the flow proceeds to step S189 to accumulate the current round of the discount policy database by one. The discount amount determination step is terminated.

Next, with reference to Figure 4 will be described a step of determining the discount amount to determine the actual purchase amount and payment.

When the discount amount is determined through the above-described steps and the actual purchase amount is determined (S191), the amount of the discount is determined by subtracting the discount amount determined from the product market price amount (S192). The payment information is transferred to the payment authority to complete the payment. (S193) Then, the process proceeds to step S194, where the actual purchase amount of the purchaser and related information are recorded in the corresponding database, and the process ends.

In the above-described embodiment, the card selected by the purchaser for determining the discount amount is a card displayed on the screen. However, the medium to be selected is not limited to the card, and any form may be used as long as the card can be selected.

In addition, the payment means is not limited to a credit card, and the communication network is not limited to the Internet, and any communication network can exchange data between the main server 1 and the purchaser.

In addition, according to the above-described embodiment, when the buyer wins the discounted amount, the buyer pays the discounted amount. However, the buyer pays the market price first and then receives the discounted amount. You can either refund the amount of the discount or earn it in the form of a reserve.

In this embodiment, the payment method selection and payment is made before the lottery step as described above, and if the discount amount is determined by the lottery, it is refunded to the buyer or accumulated in the form of reserve.

Meanwhile, in the above-described embodiment, the lottery discount method based on the determined probability has been described, but the lottery formula based on the probability of change determines the amount of discount applicable to the buyer based on the probability of change at the moment when the buyer selects the medium to be selected. It should be understood that a discount method may be used and the scope of rights of the present invention is not limited by the probability determination method used.

It is to be understood that the scope of the present invention is determined by the claims appended hereto and is not limited to the above-described embodiments, and improvements or modifications to the invention described in the claims are within the scope of the present invention. It is obvious to those skilled in the art.

According to the present invention as described above, by applying a different discount rate for each buyer can be more interesting to the purchase than the method of applying a uniform discount rate, since the state that the payment means is not open for a long time, credit information The risk of leakage of is also significantly reduced compared to the prior art.

Claims (7)

In the merchandise selling method on-line performed in an environment comprising a main server, a purchaser terminal connected to the main server and a communication network, and a payment institution server connected to the main server and a communication network, Recording information of different discounted amounts for at least some of the purchase order for the product to be sold; Receiving a purchase request of a buyer from the buyer terminal; Receiving payment information other than the payment method and payment amount selected by the buyer; Providing the buyer with a plurality of selected media for the buyer to select, If the buyer selects the selected medium, displaying the discounted amount corresponding to the purchase order of the buyer; Transmitting the discounted amount and the payment information to the payment institution server for payment by the payment means; And receiving payment completion information from the payment institution server. The method of claim 1, wherein the purchase order number is a predetermined number, and when the predetermined number is exhausted, the order number is increased by the predetermined number to rewrite different discount amounts for at least some of the increased order numbers. The method further comprises the step of selling goods online. The method according to claim 1 or 2, wherein the buyer can select a plurality of the selected medium, and when the buyer selects the plurality of the selected medium, the purchase order of the buyer is selected through one of the selected medium. And displaying the allotted discount amount. The method of claim 1 or 2, further comprising the step of recording the buyer's information when the buyer receives the discount amount. The method of claim 1 or 2, further comprising recording information of the buyer, product information purchased by the buyer, and payment amount information upon receiving payment completion information from the payment institution server. . In the merchandise selling method on-line performed in an environment comprising a main server, a purchaser terminal connected to the main server and a communication network, and a payment institution server connected to the main server and a communication network, Recording information of different discount amounts for at least some of the purchase order numbers for the product to be sold; Receiving a purchase request of a buyer from the buyer terminal; Receiving a payment method and payment information selected by the buyer and transmitting the received payment method and payment information to the payment institution server; Providing the buyer with a plurality of selected media for the buyer to select, If the buyer selects the selected medium, displaying the discounted amount corresponding to the purchase order of the buyer; Refunding an amount corresponding to the discount amount to a buyer. In the merchandise selling method on-line performed in an environment comprising a main server, a purchaser terminal connected to the main server and a communication network, and a payment institution server connected to the main server and a communication network, Receiving a purchase request of a buyer from the buyer terminal; Receiving payment information other than the payment method and payment amount selected by the buyer; Providing the buyer with a plurality of selected media for the buyer to select, Determining a discount amount based on a probability of change when a buyer selects the selected medium, and displaying the discount amount applied to the buyer; Transmitting the discounted amount and the payment information to the payment institution server for payment by the payment means; And receiving payment completion information from the payment institution server.