Online systems come from a background where there is no full evaluation of the shilling activities that take place in different auction systems. The evaluation of shilling activities goes a long way in providing for certainty in the different type of seller.
This can be achieved through the provision of the shill scores or shill ratings for each seller in an auction system. By providing the sellers shill rating the different bidders can easily make choices for the different sellers they decide to bid for their products.
Despite the increased numerous advantages of online auction there are problems that are still present, unlike in offline markets where buyers can physically evaluate the product quality and interact directly with the sellers, in online markets the buyers do not have such opportunity as the buyers only get to evaluate the product quality via the internet interface that cannot perfectly describe the products Melnik et al, The implementation of an online auction system that provides detailed seller and product descriptions results in the increased certainty of the bidders towards the choice of the products and sellers that they make.
To generate reports for each completed bid in the auction system iv. To notify the bidders of new bids made in the bids that they participate in. The successful implementation of this project results in an online auction system that allows evaluation of the product that is far much effective and that come close or equal the physical evaluation of the product. This system only accommodates the buyers and sellers that are located within Zimbabwe.
Only registered potential buyers and sellers participate in any of the auctioning process. This auction system makes use decision making assistance tool that enables the auction bidders to properly evaluate the sellers and their products to enable them to make choice of the bids to participate in and be confident with the their decision.
This chapter specifies the project aims, objectives and scope of the project so as to provide a clear picture of the project direction. It also looks at the different strengths and weaknesses of the current existing systems. We also point out the advantages of advantages of developing the new system by pointing out its advantages over the existing systems. Chapter 3: Methodology This chapter provides an overview of the different techniques and methodologies for the development of the system.
The techniques and methodologies for the development of the system are explained in this chapter including their advantages and disadvantages. It also provides justification for the chosen methodology. Chapter 4: System Analysis and Design This chapter defines how the information is to be found and the ways in which the findings are to be conducted as well as finding that which is on the ground and finding the various solutions.
It also documents the testing and other limitations that were met during the coding process. Chapter 6: Conclusion and Recommendations It provides details on what has been achieved, looks at the targeted set objectives to see if they were achieved and provides recommendations for future work. Chapter 2: Literature Review 2.
The purpose of this chapter is to outline the evolution of auction systems, explain their general structure. The system that is developed addresses the different kind of weaknesses that exist in current system thus resulting in the development of a more effective online auction system. In fact, it can be argued that the auction based electronic markets best represent the changes to business inherent in e-commerce.
Auction systems are a major component of the electronic marketplace that allow users at any site to sell and buy products. The sellers set up auctions for their different products while the purchaser who bids the highest amount wins the right to purchase the product in an auction. In general auction systems usually make use of different various agents, the commonly used kind of agents include Purchaser Agent, Seller Agent and Facilitator Agent.
Whereas the Seller Agent provides the function of registering goods for an auction to the sellers. This design maximises the probability that the product auctioned sells. The second agent is the Purchaser Agent that requires bidding to buy and it suggests a proper bidding price by analysing the bidding history of the bidding competitor.
Clients access the auction system from one of these computers. The system allows the clients to buy and sell items by means of auctions. It was overlooked as most people preferred buying using the set-price. Before the seventeenth century the few auctions that were held were sporadic.
Nonetheless, auctions have a long history, having been recorded as early as B. According to Herodotus, in Babylon auctions of women for marriage were held annually. The auctions began with the woman the auctioneer considered to be the most beautiful and progressed to the least.
It was considered illegal to allow a daughter to be sold outside of the auction method Auctions were even popular during the Roman Empire. Later slaves, often captured and they, were auctioned in the forum under the sign of the spear, with the proceeds of sale going towards the war effort.
Auctions have dramatically over the years and now auctions are carried out over the internet. There are a number of different types of online auctions which include g English auctions, descending Dutch auctions, first-price sealed-bid, Vickrey auctions. The primary auction types are the English auction, Dutch auction, first price sealed-bid auction and second price sealed-bid auction also known as Vickrey auction.
English Auctions One of the most known and commonly used type of auction is the English auction. In the English auction the items for sale is put up for auction starting at a relatively low minimum price then the different bidders are then allowed to place their bids until the auction closes. These auctions last for a fixed duration of time which can be for hours or days. Every time a new bid item is registered, the auction time period is set, the auction closes the time-out expires Dong, For this project the English auction is the type of auction that is most appropriate due to its simplistic nature which allows it to be easily understood by different people.
English auctions are the most well known form of third-party on-line auction format used and is believed to appear the most simplistic of all the different forms. The bids are open for the different possible participants to see.
In the English auction the highest bidder is the winner of the auction. The English auction is preferred by most people due to the fact that it uses a mechanism that people find familiar and intuitive and therefore reduces transaction costs. Dutch Auctions The Dutch auction is a type of descending-price auction.
The winning participant pays the last asked price. Dutch auction is also used in online auctions where multiple identical items are sold simultaneously to one or more winning bidders. It is equivalent to a multi-unit Shatz, First-Price Sealed-Bid The first-price sealed-bid auctions are auctions in which each bidder bids just once and the bid price is kept as a secret during the auction. The winner is the one with the highest bid and pays that bid. First-price sealed-bid auctions are when a single bid is made by all bidding parties and the single highest bidder wins and pays what they bid.
The main difference between First-price sealed bid and English auctions is that bids are not openly viewable or announced as opposed to the competitive nature which is generated by public bids. Vickrey Auction A Vickrey auction, sometimes known as a second-price sealed-bid auction, uses very much the same principle as a first-price sealed bid.
However, the highest bidder and winner will only pay what the second highest bidder had bid. The Vickrey auction is suggested to prevent the incentive for buyers to bid strategically, due to the fact it requires them to speak the truth by giving their true value of the item.
Multiple sellers compete to obtain the buyer's business and prices typically decrease over time as new offers are made. They do not follow the typical auction format in that the buyer can see all the offers and may choose which they would prefer.
Reverse auctions are used predominantly in a business context for procurement. Reverse auctions bring buyers and sellers together in a transparent marketplace. The practice has even been implemented for private jet travel on the online auction site Marmalade Skies Wong et al, The term reverse auction is often confused with unique bid auctions, which are more akin to traditional auctions as there is only one seller and multiple buyers.
However, they follow a similar price reduction concept except the lowest unique bid always wins, and each bid is confidential. Different types of auctions are supported, namely English auctions, Dutch auctions, 1st Price auctions, 2nd Price auctions.
The English auction is the most well-known form of auction. The item for sale is put up for auction starting at a relatively low minimum price. Bidders are then allowed to place their bids until the auction closes.
Sometimes, the duration of the auction is fixed in advance for example 30 days, or, alternatively, a time-out value can be associated with the auction. Each time a new bid is registered, the time-out is reset. The auction closes once the time-out expires Kienzle, 2.
Shill bidding is the act of introducing fake bids into an auction on behalf of the to artificially inflate the price of an item. These fake bidders who engage in shilling are referred to as shills. This online auction system strives to provide a way to determine and detect any shilling activities that may be carried out. This can be achieved by examining bidding information across several auctions and produce a score indicating the likelihood that the bidder is engaging in shill behaviour.
The major gain for the seller is the difference between the final price and the inflated price. Shills normally have the same characteristics as they all have similar goals. As a result, a shill will tend to bid more near the beginning of an auction. This entails that a shill can influence the entire auction process and furthermore shills avoid bidding towards the end of an auction as it is risky as their main goal is to avoid winning the bid.
If the shill bids an amount that is much higher than the current highest bid, it is unlikely that a legitimate bidder will enter more bids and this results in the shill winning the shill winning the bid The most extreme shill bidding strategy is referred to as aggressive shilling.
An aggressive shill usually continually outbids everyone thereby driving up the price as much as possible. The solution that is going to be used to detect the shilling activities observes the bidding patterns over a series of auctions for particular seller looking for the shilling behaviour. To determine the shill score a matrix is used that determines the shill scores for the different sellers on the online auction system.
The matrix is based on the fact that shills have a huge number of repeated failed bids on the same seller. The shill rating [y] is high for a particular shill. This allows for bidders with a small number of losses to be ignored. Before starting with the project, considerations of current existing system and their functionalities are taken into account, then decide on the kind of system architecture and software technology to use.
The first part of the project is an investigation of already existing on-line auction systems around the internet. Three famous auction systems considered for this project are eBay, uBid and Quibid. Even sellers without stores even get free listings a month under its fee structure. This type of selling has attracted many smaller scale sellers over the years but rising fees and increasing feedback and customer service requirements have alienated many.
EBay provides a lot of buyers with the convenience of shopping online. EBay also offers international shipping to many purchasers around the world. Still, whether you are buying or selling on eBay, there are a number of disadvantages that are evident and this project addresses some of these disadvantages that are presented by eBay auction. The advent of online auctions such as eBay and uBid has made shill bidding much more exploitable.
This is because it is relatively simple for a seller to register under many aliases and operate this illegal fraud. EBay has a policy for shilling that clearly outlines the penalties for shill bidding. The regular process for the bidder who suspects that that they have been shilled is to contact eBay, who then investigates the incident. With the new system it provides the shill scores for the different buyers there is no need to first make calls to make complains.
Disadvantages Feedback Ratings eBay's buyers and sellers can leave feedback about their experiences with each other. However, while buyers can give sellers a positive, neutral or negative rating plus a short comment, sellers can give buyers only a positive rating and a short comment. This presence a number of problems as there is need for a detailed feedback rating as there are different aspects of a seller that have to be looked at. The use of a positive, negative and neutral value does not give enough information about the type of seller.
The system provides a much detailed feedback scores that evaluate different aspects of the sellers and allocating scores out of ten in each aspect and the total score will be used to determine the overall feedback score for the seller.
Further, eBay uses Paypal, which is owned by eBay, as its only method of payment. Paypal charges the sellers fees for each transaction. All these fees can discourage sellers, particularly when they cut into their bottom dollar. Scam Rate On eBay if a buyer encounters a fraudulent seller, it can take a very long period of time for him to get a refund, especially if he has to wait for Paypal to arbitrate the dispute. Buyers can be scheming, Phishing schemes are also frequent on eBay users receive false emails stating that their eBay account will be suspended, directing them to a fake login page.
Once the user logs in, his login data and eBay identity are susceptible to theft. This results in lack of communication and users receive automated email responses because a direct communication link is not established.
Advantages Of Selling on eBay One of the good aspects about eBay is that you can list an item and, as long as your keywords are solid, price is fair and your listing clear, it will sell even if you do literally nothing else to market it.
People want to get their hands on this thing and interest is high. An auction would let all the interested parties bid the price up to make sure you get the maximum price for it. It provides seller and buyer protections buyers. The is more likely to be more buyers and sellers if there is less risk of them being cheated, scammed or otherwise Hooper, UBid is one of the world leading UBid is one of the leading online auction and e- commerce site that offers live auction bidding using sophisticated auction technology uBid.
The company's Internet auctions feature a rotating selection of brand-name computers, consumer electronics, housewares, sporting goods and memorabilia, and jewelry. The site specialises in excess new, refurbished and overstocks consumer electronics such as computers, electronics, home goods, jewellery, watches and cellular phones.
Sellers must be approved with the idea that the platform should avoid counterfeit, infringing, stolen or other questionable products on its platform. The prices of auctioned products increase by one QuiBids penny with each bid.
Bidding does not start until there is only 5 minutes left in the auction. The final prices are typically much lower than other auctions, but all bidders pay to bid. Losers of the auction have the option of paying the retail price, minus the cost of their bids. There are literally hundreds of auctions every day at quibids, as compared to a few or a maximum of tens of auctions on other sites. This naturally translates into a more enriching experience and bidders have more choice for what they can buy..
If you are losing too much in the bidding process, you can have that amount counted towards buying that item at the full retail price.
This is a great feature if you are bidding for something that you would even otherwise want to buy. It has representative answering questions posed at their forums and blogs, which is a good. There is no proportionate increase in number of items at the bid. This means increased competition among the bidders and a very high profit for the site, which of course means a lot of people are going to lose a lot of money here.
This needs a serious revision if they want to make any logical sense to be around. These limits seem too stringent. Penny auctions are also for fun, which means they can relax the limits for some cases at least - perhaps the smaller valued gift cards or the auction for bids packages. User Stories eBay. Michele, As shown in the table, all the three systems give the possibility to register, to login to the website and have a home page with a general description of the portal.
They offer also a personal page, where each user can check the status of their auctions or of their offers. Another characteristic of these portals is to have an item page, a page that describes each item on auction.
The search functionality is also very important: in addiction to a normal keyword search, eBay offers also the possibility to search excluding a given word, search in a given category. All the three systems give also the possibility to place a bid, to post an auction and have also some help pages that explain the aims of the portals and the functionality.
Chapter 3: Methodology 3. The term methodology refers to a systematic way of carrying out all the activities, by providing a framework of development. This chapter covers the details of the different methodologies that can be used for this project. The goal of this chapter is to explore the different kind of methodologies and come up with the most suitable methodology for developing online auction system.
Software development methodologies help the development team structure their work in a timely and effective way. There are many different methodologies used in various types of research and the term is usually considered to include research design, data gathering and data analysis. Part of the research methodology is concerned with how the research is conducted and this is called the study design and typically involves research conducted using questionnaires, interviews, observations and experiments.
The term research methodology, is also referred to as research methods, it usually encompasses the procedures followed to analyse and interpret the data gathered.
These often use a range of sophisticated statistical analyses of the data to identify correlations or statistical significance in the results Vaccaro, In computer science research methodologies can be grouped into experimental, theoretical, simulation, formal and the build methods.
In the study of computer science formal methodologies are mostly used to prove facts about algorithms and systems.
The formal methodology is a theory and mathematically based research methodology, it mostly applied to Theoretical Computer Science Johnson, This methodology does not best suite this project as it does not specifically focus on proving facts about algorithms and the system. The online auction system is not based on proving any theoretical and algorithms as it makes use of feedback scores from winning bidders the shill scores generated for each seller and information signals in determining the quality of the products and the sellers.
Experimental methodologies are broadly used in computer science to evaluate new solutions for problems. Experimental evaluation is often divided into two phases that is the explanatory phase and the evaluation phase. In an exploratory phase the researcher is taking measurements that helps identify the questions that should be asked about the system under evaluation.
In the online auction system the explanatory phase involves measuring the minimum or maximum time that should be allocated for each auction, the number of products that each seller should sell, the number of bids that each buyer can be allowed to participate in and measuring the number of times that the same product can be resold in the same auction.
Then an evaluation phase attempts to answer the questions from the explanatory phase and providing solutions for example providing the maximum amount of time that an auction is allowed to run. A well designed experiment starts with a list of the questions that the experiment is expected to answer. Experimental method requires good record keeping which makes it possible to retrieve and check them later.
The is need for great care to be taken when keeping the records as most computer science researchers tend not to careful when keeping the records. Speed is an important factor during the exploratory phase of an experimental work. Thus this phase usually proceeds with less care than it should.
Once this exploratory phase is over, a researcher should document the findings and carefully describe the experimental setup, as well as the characteristics of the hardware and software used for the evaluation phase. In the experimental methodology it is important to document and report the experimental evaluation. All the tables have been normalized up to the third normal form.
In short the rules for each of the three normal forms are as below. A relation said to be in 2NF if and only if it is in 1NF and no partial dependency exists between non-key attributes and key attributes.
A relation in 2NF is said to be in 3NF if no transitive dependency exists between non-key attributes and key attributes. The old system consists of manual operations, which is operated in a very different manner from the proposed new system. A proper implementation is essential to provide a reliable system to meet the requirements of the organizations. An improper installation may affect the success of the computerized system. The most secure method for conversion from the old system to the new system is to run the old and new system in parallel.
In this approach, a person may operate in the manual older processing system as well as start operating the new computerized system. This method offers high security, because even if there is a flaw in the computerized system, we can depend upon the manual system.
However, the cost for maintaining two systems in parallel is very high. This outweighs its benefits. Another commonly method is a direct cut over from the existing manual system to the computerized system. The change may be with in a week or with in a day.
There are no parallel activities. However, there is no remedy in case of a problem. This strategy requires careful planning. A working version of the system can also be implemented in one part of the organization and the personnel will be piloting the system and changes can be made as and when required. But this method is less preferable due to the loss of entirety of the system. It identifies the personnel responsible for the activities and prepares a time chart for implementing the system.
The implementation plan consists of the following steps. The implementation plan should anticipate possible problems and must be able to deal with them. The usual problems may be missing documents; mixed data formats between current and files, errors in data translation, missing data etc. Training the system operators includes not only instructions in how to use the equipment, but also in how to diagnose malfunctions and in what steps to take when they occur.
So proper training should be provided to the system operators. No training is complete without familiarizing users with simple system maintenance activities. Since the proposed system is developed in a GUI, training will be comparatively easy than systems developed in a non-GUI.
There are different types of training. We can select off-site to give depth knowledge to the system operators. Success of the system depends on the way in which it is operated and used. Therefore the quality of training given to the operating person affects the successful implementation of the system. The training must ensure that the person can handle all the possible operations.
Training must also include data entry personnel. They must also be given training for the installation of new hardware, terminals, how to power the system, how to power it down, how to detect the malfunctions, how to solve the problems etc.
The proposed system requires trained personnel for operating the system. Data entry jobs must be done utmost carefully to avoid errors. This will reduce the data entry errors considerably. It is preferable to provide the person with some kind of operating manuals that will explain all the details of the system.
System quality , user confidence and operating systems statistics are accessed through such technique event logging , impact evaluation and attitude surveys. The review not only assesses how well the proposed system is designed and implemented, but also is a valuable source of information that can be applied to a critical evaluation of the system.
The review of the system is highly essential to determine the future enhancements required by the system. The system can be considered successful only if information system has met its objectives. Only when the merits and demerits of the implemented system are known, one can determine what all additional features it requires are. Testing is a process of executing a program with the intent of finding an error. A good test is one that has a probability of finding an as yet undiscovered error.
The purpose of testing is to identify and correct bugs in the developed system. Nothing is complete without testing. Testing is the vital to the success of the system. In the code testing the logic of the developed system is tested. For this every module of the program is executed to find an error. To perform specification test, the examination of the specifications stating what the program should do and how it should perform under various conditions. Unit testing focuses first on the modules in the proposed system to locate errors.
This enables to detect errors in the coding and logic that are contained within that module alone. Those resulting from the interaction between modules are initially avoided.
In unit testing step each module has to be checked separately. System testing does not test the software as a whole, but rather than integration of each module in the system. The primary concern is the compatibility of individual modules.
One has to find areas where modules have been designed with different specifications of data lengths, type and data element name. Testing and validation are the most important steps after the implementation of the developed system. The system testing is performed to ensure that there are no errors in the implemented system. The software must be executed several times in order to find out the errors in the different modules of the system. Validation refers to the process of using the new software for the developed system in a live environment i.
The validation phase reveals the failures and the bugs in the developed system. It will be come to know about the practical difficulties the system faces when operated in the true environment.
By testing the code of the implemented software, the logic of the program can be examined. A specification test is conducted to check whether the specifications stating the program are performing under various conditions.
The test has revealed that the new software for the agency is capable of handling the demands at the peak time. Storage Testing: This determines the capacity of the new system to store transaction data on a disk or on other files.
The proposed software has the required storage space available, because of the use of a number of hard disks. Performance Time Testing: This test determines the length of the time used by the system to process transaction data. In this phase the software developed Testing is exercising the software to uncover errors and ensure the system meets defined requirements.
Unit testing focuses on verification of the corresponding class or Screen. This testing includes testing of control paths, interfaces, local data structures, logical decisions, boundary conditions, and error handling. Unit testing may use Test Drivers, which are control programs to co-ordinate test case inputs and outputs, and Test stubs, which replace low-level modules.
A stub is a dummy subprogram. Module is defined during the time of design. Integration testing addresses the issues associated with the dual problems of verification and program construction. System testing is used to verify, whether the developed system meets the requirements.
So the process of re-testing for rectification of errors due to modification is known as regression testing. Installation and Delivery Installation and Delivery is the process of delivering the developed and tested software to the customer. Refer the support procedures Acceptance and Project Closure Acceptance is the part of the project by which the customer accepts the product.
This will be done as per the Project Closure, once the customer accepts the product; closure of the project is started. This includes metrics collection, PCD, etc. When changes are made during the maintenance phase all preceding steps of the model must be revisited. There are three types of maintenance: 1. Adaptive Updates due to environment changes 3. Perfective Enhancements, requirements changes. Table Fig The new system has been developed with so much care that it is free of errors and at the same time efficient and less time consuming.
System is robust. Also provision is provided for future developments in the system. NET represents Microsoft's vision of the future of applications in the Internet age. NET provides enhanced interoperability features based upon open Internet standards. NET represents a great improvement. NET languages, and Visual Studio. Common Language Runtime The runtime environment provided by.
The services of the CLR are exposed through programming languages. The syntax for these services varies from language to language, but the underlying execution engine providing the services is the same. Not all languages expose all the features of the CLR. The language with the best mapping 45 to the CLR is the new language C. NET, however, does an admirable job of exposing the functionality.
NET Framework class library is huge, comprising more than 2, classes. All this functionality is available to all the. NET languages. The library consists of four main parts: 1. Data and XML classes 3. Windows UI 4. Web services and Web UI Common Language Specification The CLS is an agreement among language designers and class library designers about those features and usage conventions that can be relied upon.
CLS rules apply to public features that are visible outside the assembly where they are defined. Languages in. NET is a consumer. Visual Studio. NET Visual Studio. NET includes a range of new features and enhancements for every type of developer, and offers key improvements directed at mobile device developers and enterprise developers. The ADO. The ASP. NET classes support the development of Web-based applications and Web services.
The Windows Forms classes support the development of desktop-based smart client applications. NET is a programming framework built on the common language runtime that can be used on a server to build powerful Web applications. NET is compiled common language runtime code running on the server. Unlike its interpreted predecessors, ASP. NET can take advantage of early binding, just-in-time compilation, native optimization, and caching services right out of the box.
NET framework is complemented by a rich toolbox and designer in the Visual Studio integrated development environment. WYSIWYG editing, drag-and-drop server controls, and automatic deployment are just a few of the features this powerful tool provides. Power and Flexibility. Because ASP. NET is based on the common language runtime, the power and flexibility of that entire platform is available to Web application developers.
NET is also language- independent, so you can choose the language that best applies to your application or partition your application across many languages. Simplicity ASP. NET makes it easy to perform common tasks, from simple form submission and client authentication to deployment and site configuration. For example, the ASP. NET page framework allows you to build user interfaces that cleanly separate application logic from presentation code and to handle events in a simple, Visual Basic - like forms processing model.
Additionally, the common language runtime simplifies development, with managed code services such as automatic reference counting and garbage collection Manageability ASP. NET employs a text-based, hierarchical configuration system, which simplifies applying settings to your server environment and Web applications.
Because configuration information is stored as plain text, new settings may be applied without the aid of local administration tools. NET Framework applications as well. An ASP. NET Framework application is deployed to a server simply by copying the necessary files to the server. Scalability and Availability ASP. NET has been designed with scalability in mind, with features specifically tailored to improve performance in clustered and multiprocessor environments.
Further, processes are closely monitored and managed by the ASP. NET runtime, so that if one misbehaves leaks, deadlocks , a new process can be created in its place, which helps keep your applications constantly available to handle requests Customizability and Extensibility ASP. NET delivers a well-factored architecture that allows developers to "plug in" their code at the appropriate level.
In fact, it is possible to extend or replace any subcomponent of the ASP. NET runtime with your own custom-written component. Security With built in Windows authentication and per-application configuration, you can be assured that your applications are secure.
Language Support The Microsoft. NET are by far the most extensive of all the potential migration issues. Not only has ASP. NET Visual Basic. Net is designed to be a fast and easy way to create. NET Web applications. Applications written in Visual Basic are built on the services of the common language runtime and take full advantage of the. NET Framework. Visual Basic. NET VB. NET framework. It is fully integrated with the. NET Framework and the common language runtime,1 which together provide language interoperability, garbage collection, enhanced security, and improved versioning support.
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