Abstract

Today's electronic markets on the Internet provide substantial advantages for a single person in a "shopping from the list" scenario, which is characterized by low interaction between humans. However, by considering more interactive scenarios, e.g. window shopping, group interaction turns into a valuable and innovative element of future electronic malls.

Group InterAction (GIA) creates a more interesting shopping experience by providing a social environment. Our approach, which is overviewed in Figure 1, turns the shopper from a number in the system to an individual and allows customer and group awareness. Another objective was to add mutual customer influence to the electronic market by supporting both unintentional stimulation and intentional influence via discussion and voting. Overcoming real markets, computer-based group coordination increases team efficiency and works also over distances.

Communication enables the customer to fill individual information gaps in an efficient way. Additionally interaction makes an electronic market more attractive for the shopper. The marketer profits from a bigger amount of customers resulting from the higher attractivity and his customers are even more motivated because the shop assistants can help interactively. Last but not least, the supplier gets a new communication channel to his customers. To sum up, with group interaction the electronic market turns from an application into a social place.

1 Introduction

At all times markets have been not only places for exchanging goods and money, but also have played a major role as a center of communication between the market participants. In most of today's electronic malls, on the contrary, shoppers act in a scenario which is comparatively poor from a communications point of view [BHMR96]. Shopping in electronic markets feels much like gathering goods in a deserted deposite before paying at a banking machine. This "shopping from a list scenario" is still valuable as long as interaction plays a minor role, e.g. while ordering food from a local pizza service. However, more interactive market scenarios are rarely supported by available merchant systems.

1.1 Scenarios for Electronic Markets

Imagine it was 9 pm when Patricia remembered to buy some food she needed the next morning. She drove to the nearby regional mall and as she already knew exactly what she needed - sugar, corn flakes and nuts - food shopping was more or less a burden. Being able to order the goods via existing stores on the Internet provides substantial advantages for a single person in a "shopping from the list" scenario, which is characterized by low interaction between humans. But scenarios also exist (see Figure 2) which suggest that communication is not "just for fun", but a substantial element of traditional markets.

"Window Shopping" is a scenario where customers walk around in malls, gather information, meet other people and recognize others' activities, thus being encouraged to communicate with people that seem to share their interests, become acquainted with other market participants and being influenced by others. Today's electronic malls don't support simultaneous communication and shopping.

The scenario "Non Expert Shopping" addresses a situation in which an inexperienced shopper lacks information about a specific good or a detail of a certain market process. Here communication with other market participants provides an efficient way of gathering the missing information. Dialogs in parallel to shopping are not supported by existing electronic malls.

Additionally within "Group Shopping", a closed social group can act in parallel, thus being more efficient than a single person. However, these activities need to be coordinated most of the time to remain effective. In electronic markets there is no support of coordination yet.

Shared experience is common for traditional markets. Together with the possibilities to "take someone by the hand", an "inexperienced web user" can get support during his first time on the electronic market. The client interfaces of today's electronic markets are designed for single users.

1.2 Implementation of Support in Cooperative Market Scenarios

In order to address the more interactive aspects of shopping we decided to implement a system for "Group InterAction" (GIA) on electronic markets. Group interaction can be defined by its basic functionalities, which are in our context: User Perception, Location Chat, Acquaintance Chat and Cooperative Navigation. The design of a Client Server Architecture became the conceptual basis for the development of a demonstrator. The actual implementation of the client is a Java applet; the server runs as an additional service on an Internet server.

1.3 Profit of Interaction Support

In addition to just browsing the market, the customer can use group interaction for communication in order to get information needed to make a decision in an efficient and convenient way. Additionally, interaction support increases the attractivity of a market and serves as a competitive incentive for visiting the group enabled market. The same arguments hold true when we enable groups to interact with each other. To sum up, with group interaction, the electronic market turns from an application to a social place.

The advantages for the marketer at an electronic market place are a more customers resulting from the higher attractivity and more motivated customers because of their additional possibilities for coping with problematic situations. Last but not least, the supplier gets a new communication channel to his customers.

2 Concepts of Group InterAction (GIA)

2.1 Goals of Interaction Support

In order to enable the market participants to act similarly to the interactive market scenarios it is necessary to support group interaction [MaZi96]. At first group interaction should make shopping in an electronic mall more interesting by enriching the social environment. Our approach in turning the customer from a number in the system to an individual person was to

• add awareness of other customers to the pure representation of the market (see 2.2: User Perception),
• provide functionality for communicating with unknown customers (see 2.2: Location Chat),
• support communication within socially closed groups (see 2.2: Acquaintance Chat), thereby enabling the shopper to realize himself as a member of a group as well as an individual,
• add customer influence to the electronic market (discussion and voting are examples of intentional influence whereas stimulation works without intention). Last but not least we intended to add functionality that overcomes the limitations of reality. To
• support computer-based coordinated action of groups enhances efficiency and - overcoming reality - cooperative navigation on electronic malls also works over large distances.

2.2 Basic Functionalities of GIA

User Perception

One important prerequisite for group interaction is the support of user perception. The challenge of this basic functionality is to gather the Client's URLs and to generate the information needed to visualize the visitors. One approach in a 2D environment is the room plan metaphor. Each location, which represents a logical related set of URLs, is represented in a room plan that additionally visualizes all the visitors residing in the current location or a subordinated place.

Location Chat

The basic functionality "Location Chat" enables a user to communicate with other people probably sharing interests because they reside in the same environment (location). The simplest form of communication is the ASCII-Chat. Note that the members of one's current Location Chat group depend on the user's current location. If a user navigates to another page, the Chat members may change since the Chat group is dynamically built from the visitors of the current location. A shop assistant that visits a location can give customer support.

Acquaintance Chat

In contrast to the Location Chat, where people normally do not know each other, the "Acquaintance Chat" can be used for communication within a closed social group (e.g. friends, relatives, ...). The participants of such a chat group are independent from a member's current location.

Cooperative Navigation

Within the Acquaintance Chat Group "Cooperative Navigation" is supported. It enables the members to "beam" to a friend's current page by simply pressing a button. For Guided Tours or if a person is a non-experienced web user it is possible to follow another group member. Each time the leader moves to another page, all followers' browsers are automatically synchronized.

3 System Architecture of GIA

The GIA server manages all client information, e.g. every shopper's name and current location or information about groups and their members. The server runs as an additional service on an Internet server. The four basic funcionalities (see chapter 2.2) of GIA can be realized by three function packages:

• Client Management,
• Location and Floor Plan Management and
• Multi Group Chat Management.

Within the GIA System the market representation (HTML) is done furthermore by Web browsers. The GIA client components enhance existing browsers with the functionalities of the GIA System. To be as far as possible independent of a specific market content and design, we realized the client components as a Java applet in a HTML frame (see Figure 3).

Figure 4 gives an overview of the information streams between the browser, the giaClient component and the giaServer application. At position 1 the figure depicts the flow of log-in messages from the GIA client to the GIA server, which stores and distributes all necessary kinds of management information. The GIA server is notified (2) of client URL changes within the browser via the GIA client and is therefore able to answer client requests about the actual location of a client. In addition to this push principle, an event oriented stream of change information exists (3), which is initiated by the GIA server and is necessary for cooperative browsing. Another flow of data (4) is processed for the exchange of chat messages between groups. Apart from the GIA System there is an event triggered exchange of market data (HTML) between the browser and the markets Internet server.

4 GIA Demonstrator

The GIA demonstrators were developed to demonstrate the possibility of implementing the abstract GIA concepts and to evaluate the usability and performance of the system.

4.1 Demonstrator "Current Location"

When loading the entry page of the demonstrator the browser splits into two horizontal frames. In the upper frame the GIA-Client runs as a Java applet. In the lower frame the homepage of the demo market is loaded. Picture 5 is a screenshot of the GIA system, which was taken after the user entered our demo market. On the left part of the GIA client applet, the map provides a room overview of the user's current location (basic functionality "User Perception"). The Room Map panel visualizes not only passive market objects, but also other visitors. On the right part of the GIA client applet, the Location Chat panel is situated (basic functionality "Location Chat"). It enables the user to communicate with other people in his current environment. As soon as the user moves to a different location, his environment changes (Location Chat group and Room Map). The HTML page in the lower frame demonstrates another visualization of visitors. Here the number of "little men" running around the ball corresponds to the number of visitors in that section.

4.2 Demonstrator "Acquaintance Chat"

The second screenshot (Figure 6) illustrates the implementation of the basic functionalities "Acquaintance Chat" and "Cooperative Navigation". After a group of people met in an Acquaintance group they are able to talk to each other in a closed social environment. In contrast to the Location Chat Group, the members of a Acquaintance Chat Group do not change while moving from location to location, thus allowing them to navigate while talking to their acquaintances. A participant of this chat can also use the Cooperative Navigation functionality of the GIA system to join another group member by simply pressing the "goto" button. A person (e.g. a non experienced web user) can furthermore follow another group member to each page it navigates, by pressing the "follow" button.

4.3 Standards Used for Implementation

The GIA demonstrator was implemented based on common Internet standards [W3C]. HTML was used for the representation of the pure market objects. This description language is interpreted by WWW browsers and so visualization of the pure market objects is not a task of the GIA system. The client component as well as the dynamic client information are loaded from the server. For that reason the GIA system works without software distribution. The client component was realized as a Java applet that uses the Remote Method Invocation mechanism [SunRMI1.1] to communicate with the GIA server, which itself was realized as a Java application. The market objects frame and the client applet are connected via JavaScript and LifeConnect [NetscLC]; this connection is used to inform the client applet of URL changes.

5 Related Work

Computer Mediated Communication (CMC) and Interaction is a well established research area of information technology; it is also important for CSCW (Computer Supported Cooperative Work). We found that some of the functionalities of GIA are addressed within existing systems.

Quite a lot of ASCII-Chat Systems have been realized already. Whereas first implementations supported only one-to-one dialog situations, the IRC (Internet Relay Chat) is a broadly used group-enabled chat system. Most of the existing chat systems like IRC lack visualization of communication partners and their communication context, and also cooperative action is not supported.

The developers of WWW browsers enhance the functionality of their products with cooperation functionality. One example is "Netscape", which integrates a chat window, a sketch pad, the possibility of file transfer and browser synchronization in its "Communicator". As only two persons can use this functionality, the group oriented aspect of Location Chat or Acquaintance Chat are very restricted.

A lot of research projects deal with human interaction. User awareness and group support were also addressed within the CoBrow project [CoBrow96], whose main functional areas are Matching of Users, Group Management, Communication Tools and Collaboration Tools. The CoBrow server analyses the HTTP communication and uses the resulting information to track user's URLs. The CoBrow System does not support cooperative navigation and closed social groups.

In [PaRo96] a protocol for "User Awareness" within the Internet is presented, which is designed to become a communication standard for user aware applications within internet browsers. Group aspects are not addressed within the protocol.

6 Conclusions

Within a standard Internet environment, we were able to enhance merchant systems with Group InterAction (GIA), which is based on the basic functionalities User Perception, Location Chat, Acquaintance Chat and Cooperative Navigation. On basis of the GIA Client/Server architecture we realized a first demonstration prototype of "Group Interaction on Electronic Markets", which demonstrates how to support complex social behavior within electronic commerce scenarios.

Our ongoing work concentrates on enhancing the existing GIA capabilities with advanced functionality and to improve the system engineering. A major challenge will be to enhance ASCII chat by more structured forms of communication. We expect to use script-based support of human interaction, which serves as a trusted and complete protocol for market participants in unfamiliar or complex market situations. In addition we will also work on the integration of multimedia interface technologies like audio, video or three-dimensional market representations. Additionally a set of performance enhancing optimizations were identified and will be realized in case of serious performance problems in the future.

Although further work will be investigated to enhance the functionality of the GIA system, first evaluations within the research group showed that the current functions, architecture, performance and user interface of GIA are more than a "quick-and-dirty" demonstrator, but a ready-to-run stable prototype for a real-life environment. Although performance enhancing aspects were disregarded, the system is able to handle groups of about 20 persons adequately.

Electronic markets might never reach the charming and interactive nature of a real market place, but in addition to creating an impression of an electronic market populated by individuals and groups, we realized aspects of cooperation, which partly extend the possibilities of reality.

7 References