Computer Science

Q. Discuss the process of data mining? What are the advantages of data mining.

The process of data mining consists of three stages:
(1)The initial exploration
(2) Model building or pattern identification with validation/verification,
(3) Deployment (i.e., the application of the model to new data in order to generate predictions).

Stage 1: Exploration. This stage usually starts with data preparation which may involve cleaning data, data transformations, selecting subsets of records and - in case of data sets with large numbers of variables ("fields") - performing some preliminary feature selection operations to bring the number of variables to a manageable range (depending on the statistical methods which are being considered).

Stage 2: Model building and validation. This stage involves considering various models and choosing the best one based on their predictive performance (i.e., explaining the variability in question and producing stable results across samples). There are a variety of techniques developed to achieve that goal - many of which are based on so-called "competitive evaluation of models," that is, applying different models to the same data set and then comparing their performance to choose the best.

Stage 3: Deployment. That final stage involves using the model selected as best in the previous stage and applying it to new data in order to generate predictions or estimates of the expected outcome.

Advantages offered by Data Mining :
1. Facilitates discovery of knowledge from large, massive data sets.
2. Can be used within different application areas via. Fraud detection, risk assessment , market analysis and customer segmentation etc.
3. Technique to develop effective CRM applications.
4. Returns best results when used within data warehouse environment.
5. Used extensively in telecommunications, retail and banking & finance industry.

Q. Differentiate between data warehousing and data mining.

Data warehouse means
• Subject oriented
• Integrated
• Time variant
• Nonvolatile collection of data for management’s decisions.

It contains the bedrock data that forms the single source for all DSS processing. Data warehouses contain historical data and detailed data, they are eternally large. Different types of data warehouses.
  Financial Data Warehouses
  Insurance Data Warehouses
  Human Resources Data Warehouses
  Global Data Warehouses
 
Data Mining is an analytic process designed to explore data and then to validate the findings by applying the detected patterns to new subsets of data. The ultimate goal of data mining is prediction. The process of data mining consists of three stages:

1. the initial exploration
2. model building
3. deployment

The difference between data warehousing and data mining is that data warehousing refers to the data storage whereas data mining is a process of extracting useful knowledge from the data warehouse. Different techniques are used for implementation of these two concepts.

Q.  What is on electronic payment system? What are its types and advantages?

Electronic payment systems are alternative cash credit payment methods using various electronic technologies to pay for products and services in electronic commerce. Types: The most Internet payment method for B2C is credit cards. The concern for customers is security while sending credit card information including name, card number and expiry date through Internet.

At present most of the companies use SSL (Secured Socket layer) protocol to provide security and privacy.
Visa and MasterCard have jointly developed a more secure protocol, called SET ( Secure Electronic Transmission )
Typical Electronic payment system for EC- Electronic credit card, EFT, debit card, storedvalue card, and e-check.

Advantages
It provides good security schemes. Four essential security requirements for safe e-payments are Authentication, Encryption, Integrity, and Nonrepudiation.

SET(Secure Electronic Transmission) which is theoretically a perfect protocol.

Q. What is i) E-Cash ii) Electronic Cheques.

i) E-Cash:
E-cash is cash represented by two models. One is the on-line form of e-cash (introduced y DigiCash) which allows for the completion of all types of internet ransactions. The ther form is off-line; essentially a digitially encoded card that could be used for many of the same transactions as cash. The primary function of e-cash is to facilitate transactions on the Internet. Many of these transactions may be small in size and would not be cost efficient through other payment mediums such as credit cards These types of payments, turning the Internet into a transaction oriented forum, require mediums that are easy, cheap (from a merchants perspective), private (see Privacy), and secure (see Security). Electronic Cash is the natural solution, and the companies that are pioneering these services claim that the products will meet the stated criteria.

ii) Electronic Cheques
Another mechanism for Internet payment is electronic cheques. With electronic cheques, the payer (either an individual consumer or a business) instructs his financial institution to pay a specific amount to another part, the payee. A cheque in the electronic form means a cheque which contains the exact mirror image of a paper cheque, and is generated, written and signed by a secure system ensuring the minimum safety standards with the use of digital signature (with or without biometrics signature) and asymmetric crypto system

Q.  Define EDI. Explain the layered architecture of EDI.

Electronic Data Interchange (EDI) is used by organizations for transactions that occur on regular basis to a pre-determined format. It is one of the electronic commerce technologies.
It is used in number of trade sectors for inter-organization, regular, repeat transactions. These systems require EDI standards, EDI software, an EDI network and trading community.

Layered Architecture of EDI:
EDI is most commonly applied in the Execution and settlement phases of the trade cycle. In execution of a simple trade exchange, the customers’ orders can be sent by EDI and the delivery notification from the supplier can be electronic.

For settlement the supplier can use EDI to send the invoice and the customer can finish the cycle with an electronic funds transfer via the bank and an EDI payment notification to the supplier.
This whole cycle may be complex and other electronic messages can be included. EDI can be used for Pre-Sales transactions; there have been EDI messages for transactions such as contract but are not wisely implemented.

EDI can be used for After -Sales transactions but only if they were in a standardized format and frequent enough to justify system costs, transactions such as dealer claiming
payment for warrantee work could be possible application.