F6 ICT S3: Information Systems Development

前言：所有资料都能在网上找到，大家当作一个参考，不确定的可以找老师问。我的笔记只是集合几个网站的资料，方便大家罢了。里面经常会加一些额外资料，会加*以示提醒，此外会有多个意思或者points去解释，大家只拿自己能理解的就可以，不需要全部都背，仔细看会觉得解释都很相似。会加一些个人解释，如有语法问题，错字，错误等请大家多多包涵和欢迎指正.....

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Candidates should be able to:

(a)      state the purposes of systems analysis and design;

(b)      explain the differences between manual systems and computerized systems;

(c)      describe the duties and responsibilities of personnel in systems development information system: managers, systems analysts, and programmers;

(d)      describe the differences between types of information systems: transaction processing systems, management information systems, decision support systems, and expert systems.

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*Information System Development (ISD)

-Process whereby a work activity or larger organizational setting is facilitated by introducing a new socio-technical

information system or modifying or expanding an existing one.

-Process used in systems engineering, information systems, and software engineering for planning, creating, testing, and

deploying an information system,

>一个过程去设计新的软件/系统或者更新系统

*Information System (IS)

-A collection of hardware, software, data, procedure, and user that work together to produce quality information.

*What is System Analysis and Design (SAD)

-Examination of the business problem that organizations plan to solve with an information system.

-A problem-solving technique that improves the system and ensures that all the components of the system work efficiently to accomplish their purpose.

-A problem-solving procedure that consists of 5 phases to examine and improve an Information System.

a) Purposes of System Analysis and Design

-to produce a software system that going to support the basic functions of business transactions of an organization.

-to increase the productivity and efficiency of staff.

-to gather information about the existing system in order to determine the requirements for an enhanced system or a new system.

-to study a system or its parts in order to identify its objectives.

#答题小tips：如果问SAD的意思，可以用它的作用当definition

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(b)      explain the differences between manual systems and computerized systems

        *Manual Working Systems

-A conventional working systems
-A bookkeeping system where records are maintained by hand, without using a computer system.

-Disadvantages:

~Inconsistency in data entry

~Large ongoing staff training cost (to ensure the staff is following the correct procedures)

~Reduce information sharing and customer services

~Lack of security

~Cause data duplication

~Time consuming

~Costly to produce reports

*Computerised Systems

-System that includes usage of hardware, software, procedures, users, and the organized data for generating information to support the organization's objectives.

-Advantages:

~Can handle works more efficiently (Able to produce accurate results for users to make a correct decision)

~Save time and money

~Data is easily edited

~Able to share data 

-Disadvantages:

~Has potential for system crash that causes data loss.
~Risks of malicious hack

#如果问差别，一个手动，一个电脑操作。各自的好处/坏处只是参考，并不是绝对答案。

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c)      describe the duties and responsibilities of personnel in systems development information system: managers, systems analysts, and programmers

       Information System Managers

-Officers whose responsible to plan, observe and coordinate every information resource of an organization.

-Responsible for projects being delivered on time and on budget.

-Observe and coordinate works carried out by the system development team.

System Analysts

-Computer professional who studies the information system of an organization to decide the necessary action to be taken 

-Study how to use information and communication technology to improve the organization's information system.

-Analyse and determine the system requirements

-Design a suitable system that will meet the client's needs.

System Programmers

-Involve in program coding and testing, maintenance of information system, and monitoring the database system to make sure it works correctly.

-Person that works to write programs that executes specific database functions according to specifications required by the database administrators or users.

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d)      describe the differences between types of information systems: transaction processing systems, management information systems, decision support systems, and expert systems

       *Transaction Processing Systems (TPS)

-System that record day to day business transactions of the organization

-System that collects, store, modify and retrieve the transactions of an organization

-Exp: Payroll Systems, Airline Booking Systems, Order Processing Systems

>帮忙收集，储存，寻找等交易资料

*Management Information Systems (MIS)

-Information system that generates accurate, timely, and organized information to make decisions

       -System that provides useful, complete, and accurate information to support the decision-making process.

-Uses output from TPS as input

-Exp: Budgeting systems, Sales Management Systems

>提供和处理有用的资料帮忙做决定

*Decision Support Systems (DSS)

- An interactive information system that analyzes large volumes of data for informing business decisions.

-A computerized-based information system that organizes, collects and analyzes business data that can be used in decision-making activities for the management, operations, and planning in an organization or business.

-Handle unstructured decision-making.

-Exp: Logistics Systems, Financial Planning Systems.

>分析处理信息帮助做决定

-Advantages:

~Save time and reduce cost

~Enhance efficiency

-Disadvantages:

~Information overload
~Status reduction

*Expert Systems (ES)

-System that makes decision similar to decision made by specialist

-Consist of database that stores experts; experiences and calculations in fields that they majored in.

-A computer system that emulating the decision-making ability of human expert.

-Components (考试曾问过):

~Knowledge base

~Search/Inference Engine

~User Interface

-Advantages:

~Reduce cost

~Reduce danger

~increase availability

-Disadvantages:

~Can make absurd errors if data is entered incorrectly.

~Does not provide creative response in certain situations

~Relies on rules and knowledge.

Difference Between DSS and ES

DSS	Expert System

It facilitates decision-making.	It automates decision-making.
The decision environment is unstructured.	The decision environment have structure.
It extracts or gains knowledge from a computer system.	Inject expert knowledge in to a computer system.
Characteristics of the problem domain is complex and broad.	In this, it is limited and specialised.
Type of data manipulation is numeric.	Type of data manipulation is symbolic.
It has limited capacity.	It has a full capacity.
It uses goals and system data to establish alternatives and outcomes, so a good decision can be made.	The expert system can eventually replace the human decision maker.

#搬运自https://www.geeksforgeeks.org/difference-between-dss-and-expert-system/?ref=rp

Differences Between MIS and DSS

PARAMETER	MIS(MANAGEMENT INFORMATION SYSTEM)	DSS(DECISION SUPPORT SYSTEM)
1. Main task	Identifies information requirements.	Develop certain tools for using the decision process.
2. Main stress	Main stress is on efficiency.	Main stress is on effectiveness.
3. Type of database used	Uses corporate database.	Uses a special database.
4. Data related task	Data storage is of great importance	Main emphasis is on data manipulation
5. Dependency on	Very much dependent on computer	dependent on management judgment.
6. Access to data	Indirect access of data by provided	Management enjoys direct access
7. Principal use	Principal use is control	Principal use is planning, staffing, decision making.
8.Created/developed by	Constructed by vendors or information specialists	Created by users alone or with specialists.
9. Types of users	Middle level, lower level, sometimes senior executive	Analysts, professionals, managers.
10. Main focus	Focuses on information processing.	Focuses on decision support, analysis.

#搬运自https://www.geeksforgeeks.org/difference-between-management-information-system-mis-and-decision-support-system-dss/?ref=rp

Differences Between TPS and MIS

(1) 
-MIS provides information about internal operations to managers for decision making, planning, and analysis. The system helps to compare this data to facilitate decision-making and answer questions.
-TPS, on the other hand, performs routine operations for supervisory executives which include storing, retrieving, possessing creating, and formatting data. The users of TPS come on the lowermost level in the management hierarchy while the users of MIS are the mid-level managers.

(2)
-The input activity of TPS involves data entry, transaction processing, TPS file and database processing, and TPS documents and report generation.
-The activities performed by MIS are taking high volume transaction level data as an input and then processing this input based on simple models. The outputs of MIS are the summary reports that are used by the middle managers.

(3)
-MIS uses compressed and summarized data provided by the TPS,
-TPS deals with raw data.

(4)
-TPS generates action documents (for example purchase orders and paycheques), information documents (for example sales orders and sales receipts), control listings that include transaction logs and turnaround documents. All these documents do not help in decision making. 
-While the reports produced by MIS are scheduled reports (monthly financial statements) and exception reports (for example credit reports).

(5)
-TPS provides information to the MIS and DSS (Decision Support Systems) 
-MIS provides information to ESS (Executive Support Systems) and DSS.

#搬运自https://qsstudy.com/business-studies/how-does-mis-differ-from-tps

#历年考题会发现有好几年有问之间的差别，意思等，所以这四个要好好理解。