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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 10-1 Chapter 10 Developing and Acquiring Information Systems “Pay attention to what works, and do that.” Tom Anderson, Co- founder of MySpace “Pay attention to what works, and do that.” Tom Anderson, Co- founder of MySpace
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Customized Vs. Off-the-Shelf Software 10-2 Customized software Customizability Problem specificity Off-the-shelf software Packaged No specific tailoring Less costly Faster to procure Combining customized and off-the-shelf software
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Information Systems Development 10-3 Systems analysis and design Process of designing, building, & maintaining info. systems Systems analyst Early IS development Very unstructured Programmer skills varied 1990s - Evolution to IS development as “discipline” Software engineering Benefits Easier to train systems analysts Systems would be easier to maintain
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 IS Development in Action 10-4 Structured process moving through steps Problem decomposition Problems broken up into simpler, smaller pieces
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 The Role of Users in Systems Development Process 10-5 Systems users are involved in all phases of system’s development process Mutually respectful relationship necessary Organizational members need to understand the development activities well (SDLC) Systems development life cycle
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Phase 1: Systems Planning and Selection 10-6 Identify and select potential projects Projects critical to mission, goals, and objectives Selection process varies among organizations Formal information systems planning process Ad hoc process Differential focus of projects based on selection source
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Evaluation Criteria for Systems Projects 10-7 Different criteria may be used to evaluate projects Usually multiple criteria examined for each project
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Phase 2: Systems Analysis 9-8 Designers gain understanding of current processes
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Key Elements to Development of a System 10-9 1. Collecting Requirements 2. Modeling Data 3 & 4. Modeling Processes and Logic
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Collecting System Requirements 10-10 Most important activity Requirements collected from: People: Users & Managers Business processes Documents System requirements collection techniques: Interviews Questionnaires, Observations Document analysis
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Critical Success Factors Methodology 10-11 Critical success factor (CSF) Something that must go well to ensure success Systems analyst interviews individuals to identify their CSFs Organization-wide CSFs are identified
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Joint Application Design (JAD) 10-12 Special type of group meeting Reduced time for requirements collection
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Modeling Organizational Data 10-13 Systems analysts need to understand what data will be collected Data modeling tools Entity-relationship diagram
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Modeling Organizational Processes & Logic 10-14 Data flows Movement of data through an organization Process Logic The way in which data are transformed
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Designing Forms, Interfaces & Dialogues 10-15 Designing forms Forms are business documents Contain some data Collect additional data Designing Interfaces and Dialogues Users interact with IS through various interfaces Example: text-based, menu-driven User interface standards Mac and Windows operating systems Graphical user interface (GUI)
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Designing Reports, Databases and Files Designing reports Reports are business documents that contain predefined data Designing databases and files Data modeling tools used for gaining understanding Conceptual model —ERD Physical data model—more detailed 10-16
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Phase 4: System Implementation and Operation 10-17 Transformation of design into a working information system
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Software Programming and Testing 10-18 Programming Transforming the system design into a working computer system Processing and testing should occur in parallel Tests conducted before system completion
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 System Conversion 10-19 Installation of the new system
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Documentation 10-20 Information system documentation Details of the inner workings of the system Written by programmers User-related documentation Written by professional technical writers User and reference guides User training and tutorials Installation procedures and troubleshooting suggestions
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 User Training and Support 10-21 Self-paced training and tutorials the least expensive One-on-one training the most costly Ongoing education may be necessary
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 System Maintenance 10-22 Typically starts after software is installed The largest part of system development effort occurs at this stage
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Types of Software Maintenance 10-23 Corrective maintenance given higher priority Corrective maintenance most likely to occur after initial system installation
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Prototyping 10-24 Used for development of less structured information systems Hard to specify Constantly changing Trial-and-error approach
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Rapid Application Development 10-25 Four-phase system development methodology Requirements planning User design Construction Move to the new system RAD becomes radical in phase 2; intensive user involvement System builders cycle between phases 2 and 3 until system is built
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Object-Oriented Analysis and Design (OOA&D) 10-26 OOA&D approach done in terms of common modules (objects). Combines: the “what” (data) with the “how” (operations to be performed) Different methods used to better integrate various aspects of the system Preexisting objects can be used or adapted
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Need for Alternatives to Building Systems Yourself 10-27 Building systems in-house is always an option, unless you are faced with: 1. Limited IS staff (too small; otherwise occupied) 2. IS staff has limited skill set 3. IS staff is overworked (too many projects; too little time) 4. Problems with performance of IS staff Derailed IS departments Staff turnover Changing requirements Shifts in technology Budget constraints
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 1. External Acquisition 10-28 Purchasing an existing system is similar to the process of deciding which car best meets your needs Steps in External Acquisition Competitive bid process (find the best system for lowest possible price) 1.Systems planning and selection 2.Systems analysis 3.Development of a request for proposal 4.Proposal evaluation 5.Vendor selection
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Request for Proposal (RFP) 10-29 A report detailing system requirements sent to prospective vendors Proposal Evaluation An assessment of proposals received from vendors May include system demonstrations System benchmarking Standardized tests to compare different proposed systems Common system benchmarks Response time given a specified number of users Time to sort records Time to retrieve a set of records Time to produce a given record Time to read in a set of data
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Vendor Selection 10-30 Usually more than one system will meet the criteria Need to prioritize/rank the proposed systems Best ranking system is chosen Issues to Consider Managing Software Licenses Shrink-wrap and click-wrap licenses Enterprise or volume licenses Application Service Providers (ASP) of SaaS (Software as a Service)
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 2. Outsourcing 10-31 Turning over responsibility for some or all of an organization’s IS development and operations to an outside firm Your IS solutions may be housed in their organization Your applications may be run on their computers They may develop systems to run on your existing computers (within your organization)
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Why Outsourcing? 10-32 Cost and quality concerns— higher quality /lower cost Problems in IS performance - problems meeting acceptable standards Supplier pressure —aggressive sales force convinces IS outsourcing Simplifying, downsizing, and reengineering— focusing on core competencies Financial factors—liquidation of IT assets Organizational culture—no political ties Internal irritants - bad relationship w/ IS dept.
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Managing the IS Outsourcing Relationship 10-33 Ongoing management of an outsourcing alliance needed 1. Strong, active CIO and staff 2. Clear, realistic performance measurements of the system 3. Multiple levels of interface between customer and outsourcer Full-time relationship managers should be assigned
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 3. End-User Development 10-34 Growing sophistication of users Future users of the system are the system’s developers Application development may be faster No need to rely on external entities Benefits of End-User Development Cost of labor (reduced by end user tools) Long development time – Users’ needs may change End-user development may “skip” the queue – More timely Better at responding to changing needs No need to wait for IS staff to make updates Reduce work overload of IT staff – shift to end users
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Encouraging End-User Development 10-35 Fourth-generation development (4GL) tools have made end-user development easier Categories of 4GLs: 1. Personal computer tools Example: spreadsheets, DBMS 2. Query language/reporting generators Improved searching 3. Graphics generators Extracting information and presenting it in graphical format 4. Decision-support or modeling tools Support for analysis of more complex, multidimensional problems 5. Application generators Analysis specifications given in user-friendly language
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 End-User Development Pitfalls 10-36
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Microsoft’s Surface 10-37 Technology shown on CSI Miami Users grab data with fingers Natural gestures Touch Place objects on screen to get information about them Cell phones MP3 players
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IS Today (Valacich & Schneider) Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall 10/17/2015 Hackers, Patches, and Reverse Engineering 10-38 Hackers Break into computer systems to steal or manipulate data Look for security holes Study applications until they discover a hole Follow other hackers’ guidelines Reverse engineer patches Patches Released by software producers Plug security holes
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