PSM

study design the methodology comprises four stages: **analysis**, **design**, **development** and **evaluation**.
 * The Problem Solving Methodology is integral to Information Technology studies. It is a methodology for systematically creating solutions to information problems. As applied in the

[[file:PSM.ppt]]
|| > These requirements can be classified as being: > Tools to assist in determining the solution requirements include Planning how the solution will function, and the appearance of the resulting information. The solution design typically involves identifying what specific data is required and how the data will be named, structured, validated and manipulated. Typical design tools for this purpose include Solution design also involves, where appropriate, showing how the various components of a solution relate to one another, for example Typical design tools used to show relationships include Planning the solution also involves determining the appearance of information generated from a solution. This typically involves identifying the position of text, images and graphics, font sizes, colours and text enhancements. Design tools used for this purpose include Determining the evaluation criteria. What measures will be used to judge whether or not the solution requirements have been met? These criteria should relate to the solution requirements identified in the analysis stage. || Explore the following presentations for more detail on each of the phases of the PSM.
 * ====__**Analysis involves:**__====
 * Determining the solution requirements.
 * What information does the solution have to provide?
 * What data is needed to produce the information?
 * What functions does the solution have to provide?
 * **functional**, namely what the solution is required to do (e.g. calculate age from DOB, produce an invoice), and
 * **non-functional**, which describes the attributes or qualities the solution should possess, such as
 * user-friendliness,
 * reliability,
 * portability,
 * robustness,
 * maintainability.
 * context diagrams ,
 * data flow diagrams and
 * @use case diagrams
 * Identifying the constraints on the solution. What conditions need to be considered when designing a solution? Typical constraints include cost, speed of processing, requirements of users, legal requirements, security, compatibility, level of expertise, capacity, availability of equipment.
 * Determining the scope of the solution. What can the solution do? What can't the solution do? What are the benefits of the solution to the user? The scope states the boundaries or parameters of the solution. Benefits can be stated in terms of their efficiency and effectiveness.Analysis typically answers the 'what questions' - what will solve a problem, given particular circumstances? What benefits will the solution bring to the user? ||
 * ====__**Design involves:**__====
 * data dictionaries and data structure diagrams,
 * input-process-output (IPO) charts,
 * flowcharts,
 * pseudocode,
 * object descriptions.
 * web pages,
 * style sheets,
 * scripts;
 * queries,
 * forms,
 * reports;
 * modules,
 * procedures,
 * functions.
 * storyboards,
 * site maps,
 * entity-relationship diagrams,
 * data flow diagrams,
 * structure charts,
 * hierarchy charts,
 * context diagrams,
 * use cases.
 * layout diagrams,
 * annotated diagrams/mock ups.
 * ====__**Development involves:**__====
 * Electronically manipulating (or coding) data to 'build' or create the solution following initial designs. Where appropriate, internal documentation is also written, which documents the functioning of the solution.
 * Validation to check for the reasonableness of data being input. Validation can be both manual and electronic. Proofreading is a manual technique and it occurs when data is entered directly into the solution and remains fixed, such as in a web page. When the validation process has been built into the solution (electronic technique), then its effectiveness is determined through the testing activity.
 * Testing whether the solution does what it was intended to do. This activity typically involves:
 * establishing what tests will be conducted
 * determining what test data, if any, will be used
 * determining expected results
 * conducting the test
 * recording the actual results
 * correcting any identified errors.
 * Writing documentation to support the use of the solution. ||
 * ====__**Evaluation involves:**__====
 * Evaluation finds out how well the solutions meets the demands expected of it during analysis
 * It is **not** the same as testing which determines whether the solution works or not.
 * Determining a strategy for finding out the **extent to which the solution meets the required needs**. Typically this would include
 * specifying a timeline
 * outlining what data will be collected and by what methods and techniques, and
 * how the data relates to the criteria, which were developed in the designing stage.
 * Reporting on the extent to which the solution meets the requirements of the user. It usually takes place after the solution has been used by the user/client and is based on the criteria developed in the designing stage.
 * Evaluation happens after the new or modified system has been put into regular use.
 * Evaluation is based on criteria that were established during design (or analysis) ||
 * [[file:PSM1-Analysis.ppt]]Analysis ** - defining what the problem is and what the solution should be able to do (also see [[file:PSM-Analysis-Activities-v2.ppt]]Analysis Activities)
 * [[file:PSM2-Design.ppt]]Design** - working out how to achieve the goals laiddown during analysis
 * [[file:PSM3-Development.ppt]]Development ** - building, testing and documenting the solution
 * [[file:PSM4-Evaluation.ppt]]Evaluation** - seeing whether the solution is achieving the goals it was expected to achieve

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