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Systems Requirementsand Prototyping

Idea Group Publishing

Vincent C. Yen



Systems Requirements and Prototyping 1

Systems Requirements and PrototypingVincent C. YenWright State University

Executive Summary

This case study is based on a multi-year information systems plan for a marketing firm. Initially,the investigation was enterprise-wide. We describe the critical components of the enterprise system,

including the software and hardware architectures. For the application systems, the accounting systemand the job scheduling system receive top priority. Since the accounting system was a commercial off-the-shelf product, our focus was on the development of the job scheduling system. We explain themanual job scheduling process and how the automated system might be developed. The justificationfor adopting Microsoft’s Access, SQL server, Exchange, and Project as the development tools ispresented. Microsoft Access was used just for the prototyping. Eventually, the job scheduling systemwill be implemented on the Project software with some rewriting of Visual Basic codes.

To date, a prototype using Access had been developed and demonstrated. It received favorablecomments and has been approved for the next development phase. The case study concludes withremarks on the advantages, issues and lessons learned from the project.

Background

The subject of our study is a reputable market research firm that spans more than sixty years. Thefirm is employee owned. Clients of the firm include well-known names in business and Fortune 500companies. The firm maintains sales offices in Atlanta, Boston, Cincinnati, Dallas, Detroit, LosAngeles, New York, Philadelphia, and San Francisco. The company had a mission “to help clientsmeasure and monitor customer needed and requirements in order to provide a fact-based foundationfor continuous quality improvement efforts focused on enhanced customer satisfaction and retention.”Currently, the firm offers a variety of services; including:

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IDEA GROUP PUBLISHING

1331 E. Chocolate Avenue, Hershey PA 17033-1117, USATel: 717/533-8845; Fax 717/533-8661; URL-http://www.idea-group.com

Vincent C. Yen is associate professor of management science and information systems at Wright State UniversityCollege of Business Administration. He received his Ph.D. from the Ohio State University in operations research.

His research interests include strategic information systems planning, determination of systems requirements,systems development processes, decision support systems, fuzzy control, and fuzzy decision–making. He and Prof.

H. Li co–published a book in 1995 entitled “fuzzy sets and fuzzy decision–making” by CRC Press.



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1. Assessment of internal and/or external client profile.2. Analysis of performance goals at managerial and operational levels, products and services, and

customer satisfaction.3. Assistance in design, implementation, and training of program evaluation processes.

All of these services involve data collection and analysis. For data collection, the company offers:

• Telephone and mail surveys• Personal in-depth interviews and group sessions• Comment cards in-room, point-of-transaction or with product• Traditional in-person focus group discussions• Teleconference focus group discussions• Benchmarking visits to best in class companies• Mystery shopper and quality audits of performance• On-site visits to customer locations to facilitate client/customer team meetings

Usually the data needed by a project requires a combination of the above activities. The designand analysis of data were managed by the statisticians of the company, many of whom hold advanceddegrees. The company strives to produce quality services for its clients corresponding to the missionstatement.

The Organizational Structure

The organization of the company was straight forward. Units of the organization were setup byfunctions. The president of the company directly manages: administrative division (human services,accounting, computer operations, etc.), marketing division, consulting/analytical service division(data analysis), research service division (managing project and report production), customersatisfaction division, and the customer research division. A number of departments may exist withineach division. For example, the human services department was a branch of the administrativedivision.

Current Information Systems

The company had a small systems department responsible for maintaining hardware andsoftware operations. It did not have staff to support information systems development. Installedhardware included Windows-based personal computers, Sun workstations, and Macintoshes. Localarea networks were installed, and remote connections were available between the sales office and the

corporate office. They use four different operating systems: DOS, WINDOWS, UNIX, and Apple’sSYSTEM 7.

The various commercial software used were routinely dedicated to a single purpose or function.For example, SAS was used as the statistical analysis system, and ACE was an automated costestimating system developed by end-users with Foxpro. With the exception of the accountingdepartment (whose systems and its support were out-sourced), all other applications were eitherpurchased or developed by in-house end-users. Because the company did not have a softwareprocurement policy, different word processors, spreadsheet programs, and database software co-exist.For example, Sybase, Foxbase+, Foxpro2, and Paradox were databases used by the company. Due todifferences between the files’ data format, it was frequently difficult to exchange data betweenapplications. The applications developed by end-users were created to provide a solution to a




particular operational problem. For example, end-users have used Foxpro in developing a costestimating program, a weekly activity report program, and a job order information database. Theseapplications were ad-hoc in nature and generally were both ill-designed and isolated.

The Management Initiatives

The firm’s arena of market research had been booming in the last few years. Very often, thecompany receives more than ten job orders a day. Managing these projects becomes more demandingboth in accountability and timing. Recognizing the rapid advancement of information technology andits potential impact to the service industry, the firm decided to investigate opportunities in IT that mayimprove its competitiveness. Because of limited in-house IT capabilities, in the spring of 1993, thefirm issued a request for proposal with the following stated objectives.

1. Improve the efficiency of the project management and financial accounting processes.2. Improve the data transportability and the applications integration across the diverse platforms and

operating systems.

3. Maximize the efficiency of existing data networks.4. Explore new information technologies for long-term productivity improvements.

In short, the management of the firm was interested in improving its productivity and efficiencythrough streamlining the existing information system, while selecting an information systemsarchitecture for long-term growth. After a lengthy search process, a consulting company was given thecontract. The contractor assembled a team of investigators consisting of a systems analyst, a computerengineer, and a programmer to work with the project. On the company side, a project coordinator wasassigned to work with the team. The coordinator was a knowledgeable staff member who was familiarwith the company operations and capable of answering many questions. The appointment of acoordinator had benefited the company and the project team immensely. Following the systemsdevelopment life cycle methodology, the project team’s first major task was the requirements analysis.

Defining Requirements

Methodologies

The first phase of systems development was requirement analysis. The team needed tounderstand how the existing system works. The data and knowledge gained through the analysis willserve as the basis for defining system boundaries, project scope, and the new system features andfunctions. However, in order to obtain the right kind of information, it must be carefully planned. Theteam proceeded with several information collection techniques, such as structured interviews, criticalsuccess factors (CSF) analysis, joint application development (Wetherbe, 1991), and documentreviews.

To facilitate the data/information gathering, the company established a cross-function advisorycommittee comprised of departmental chiefs, division heads, or their representatives. The team hadseveral meetings with the committee, including a brain storming session about the company’s businessoperations and procedures. These meetings provided the team members with an overall conceptualbusiness model and information of how the existing “system” works.

More detailed information about the existing system was pursued by: (1) interviewing themembers of the advisory committee, (2) studying the employee job specification handbook, and (3)



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reviewing current information systems. During this process, the team collects sample forms, reports,business procedures, information systems documents, etc.

To find out the information requirements at the managerial level, the team conducted a structuredsurvey according to the concepts of business systems planning, critical success factors, and end/meansanalysis. The survey had about forty-five participants including members of the advisory committee.Participants were given two weeks to respond the questionnaires. The questionnaire consists of questions each with a maximum of five open-ended sub-questions. As a result, a wealth of informationwas collected. The data set reveals the information systems requirements of the company and servesas the basis for the design of the firm’s information system architecture.

Techniques used so far for information gathering or requirements identification may still leaveout certain activities/interfaces between functional areas. For this reason, the team conducted two jointapplication development (JAD) meetings with the members of the cross-function advisory committee.JAD meetings were not only capable of eliciting information of importance to two or more functionalareas but also capable of producing the desired new system functions or characteristics (e.g.,scheduling/job tracking systems).

Survey Results

The survey participants were very cooperative, they responded to each question whenever theycould. The enthusiasm was probably due to the common desire to achieve a higher level ofproductivitywhile simplifying the operational process. Upon analysis of the survey, it was clear that the companyneeded a comprehensive information system, including but not limited to, job tracking, accounting,scheduling, experience database, time keeping, and data networks. The questions based on the CSFconcept were given to middle level managers and staff. The following list highlights some salientinformation systems requirements perceived by the management:

1. Up-to-date information on the progress and the cost of an active project.2. Accessing schedules of all persons working on a particular project.3. Consistent estimated results from ACE (automated cost estimating software).4. Complete information on the client requirements and expectations.5. Internal communication.

In addition to the survey results, separate findings on accounting, data networks, job tracking,scheduling, experience database, and time keeping were documented, along with an enterprise-widedata flow diagram in the Phase I report. The report points out many information systems worthy fordevelopment, including: sales and marketing support, cost estimating, financial accounting, jobcosting, job order, job tracking, time reporting, job scheduling, and progress reporting. Upon

evaluations by the company staff, the firm gave the accounting system the first priority. This wasbecause the company wants to be in full control of the accounting data as opposed to the current out-sourced service that did not permit easy access of required data. In addition, there were manyaccounting packages which were immediately available, reasonably priced and meeting their needs.After a detailed comparison of features and costs among several major accounting packages, thecompany purchased the Windows-based Platinum Accounting Systems (compatible with manypopular databases like Foxpro and Access). The compatibility feature was important becauseotherwise, accounting data could not be easily shared with other users of the company.

After the purchase of the accounting system, work on data conversion, the system installation,the system testing, and end-user training took an extended length of time. Since Platinum provided allthe services needed by the company, the consulting team did not involve in the implementation of the




system. When the new accounting system was successfully completed, in the spring of 1995, thecompany wants to proceed with the computerized job scheduling system because of its practical andstrategic value.

Current Job Scheduling System

The current job scheduling system relies, for the most part, on paper, pencil, telephone or e-mailcoordinations, and schedulers’ judgment. There were several databases supporting the job scheduling,for example, the job order database, and the experience database. The job order database consists of a client file and a job file. The client file had all pertinent data about the client, while the job file containsrecords about the job’s survey research methods, field survey dates, contract price, etc. Scheduling wasentirely manual. Since these databases were not properly designed and normalized they subject to dataredundancy and anomaly problems. In this section, we describe the current job scheduling system.

Marketing

The company’s account executives (AE) were responsible for the sales or marketing efforts of the company’s services. Account executives were expected to contact all prospective clients andprovide them with assistance in determining and refining research objectives, designing appropriateresearch plans, and presenting research results and recommendations. In addition, AEs were respon-sible for providing a full-range of research expertise and to manage client relationships while meetingspecific sales and profitability goals. Normally, after several meetings with his/her client, the AEs havedetermined critical requirements of the client’s potential research project, such as objectives of theproject, types of sampling method (e.g., mailing, telephone, interview), sample sizes, tabulation of survey results, statistical analysis, project start date, project ending date, and graphical representation.Requirements of the project were used to generate an estimate of the cost and time for the project. The

project’s cost and time estimates were then sent to the client for approval. Once the project was solda unique job number for the project was created by the research services division and this number wasalso used by the accounting department to keep track of the project payments and costs of companyresources.

Estimating Cost and Completion Time

Before the closing of a job AE must provide the client with an estimate of the cost and completiondate of the job. A prompt response of the cost and completion date will generally lead to an earlier clientdecision on the job. These estimates were currently given by the experienced staff and the ACE(automated cost estimating) system. The present ACE system was inadequate in that (1) it onlyprovided estimates for a small subset of tasks, (2) estimates were not within the reasonable range of accuracy, and (3) it did not update automatically when the new project data were entered.

The ACE system demonstrates that the company was aware of the value of the past projectexperience. Apparently, they hope one day ACE would be capable of generating the estimates for thecost, labor, and time of a project automatically. This was a difficult, if not impossible, task. But, therewas no disagreement that the present ACE system could be potentially upgraded to a much usefuloperational and competitive information system. Consequently, ACE was recommended as one of thehigh priority projects.



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The Experience Database

The database used by the ACE system was called the experience database because it was adatabase of past projects. The experience database provided historic data for the costs, labor time,duration, and research design of the past projects. Since similar projects share many commoncharacteristics the experience database was valuable for developing standards for them. The develop-ment of standards requires the use of statistical techniques. The standard time and cost for each task not only could be used for the price quotes of new projects but also could be used for scheduling newprojects. Unfortunately, the experience database was not computerized at this time. The existingautomated cost estimating (ACE) program uses a limited number of past case data as the basis of estimation. Thus, the estimates provided by the experience database may be quite inaccurate. Thisexplains why staff must use their judgment to manually make adjustments and modifications for the

job schedules.

Senior Account Managers (SAM)

Once a new project was sold, senior account managers (SAMs) assume project managementresponsibility to oversee all facets of a research study from questionnaire design, cross-tab planning,report compilation to analysis and interpretation of research data. Thus, following the job numbercreation, SAM will produce an initial project schedule with several critical due dates assigned, e.g.project starting date, project finish date. The critical due dates were referred to as milestones of aproject, they also include the field survey start date, and the field survey ending date. This was becausethe survey was the heart of the project, it carries much information about their products or services inthe market place. Clients were eager to see the raw survey results before the sophisticated statisticalanalysis because the raw results could provide the initial confirmation about the survey objectives.

The completed preliminary job schedule was sent to various departments by e-mail. Departmentsassign its staff to the job schedule on a task by task basis. In the event that departments cannot scheduledtasks without impacting timely completion of milestones, then the departmental scheduler (normallythe head of the department) will have to work out a revised job schedule with a SAM. Obviously, sucha job scheduling system was quite labor intensive and chaotic when the number of daily job orderswere large.

The Case of the New Scheduling System

The new job scheduling system was considered as a competitive information system by themanagement. The decision to develop the scheduling system had led to several meetings between thedevelopment team and the firm’s sponsors. These meetings have produced the following set of objectives for the new scheduling system:

1. Provide for standard job inputs.2. All schedules should be available online and real time. Changes will be restricted to those that have

permission to do so.3. Automatically adjust the time elements of all related tasks due to changes of task durations, or

resource utilization and availability.4. Monitor costs and resource utilization.5. Produce job status reports.




6. Provide links with the accounting system.

Before proceeding, it was made clear that the new scheduling system will seek for maximizingthe automation of routine scheduling operations, not for optimizing the resource allocation purpose.The reason was that the latter problem did not have easy solutions for large scheduling projects.

An Overview of the System

There were many options capable of achieving the above objectives, for example, reengineeringthe current system. However, after a number of interviews, it was clear that users would like to preservethe essential scheduling process as described in Section 3. The reason for preserving the currentprocess might be due to the comprehension of the existing system and the unwillingness of taking risks.

Before developing the system the manual process must be clearly defined. Studies of the currentprocess suggest that a structured three-level cooperative model was the underlying system framework.At level one, the top level, for each job proposal the main project scheduler (PD or SAM) will use datafrom the estimates of ACE, the judgments of AEs and SAMs, clients requests, etc., to determine themajor milestones and the associated due dates of the job. The output of this level was the initial jobschedule. Then, through e-mail (Microsoft Exchange), the initial job schedule was sent to therespective departments, which was level two. The department managers allocate their resources to theinitial job schedule from the department’s resource schedule (that was a combined individual staff schedule and time sheets of actual time worked). The output of the second level was either a completedschedule meeting all critical due dates or an incomplete schedule. In the latter case, they were resolvedby juggling resources and due dates until all parties will agree. So resolving a scheduling conflict wasan iterative process between the department managers and the main project scheduler. It should bepointed out that the conflict was inevitable because the main project scheduler tends to go along withthe customer demands in closing a sale. Finally, the level three was the individual staff schedule

including the time sheet processing. However, the individual at the third level may not be an internalemployee, because he/she could be a contractor responsible for telephone surveys, mall surveys, andmail surveys. The scheduling at the survey centers or at the contractors level did not belong to the scopeof this project.

Evaluation of Alternatives

How should the system be developed? The team considered three typical alternatives: (1)developing from scratch using the system development life cycle methodology, (2) purchasedpackage, and (3) prototyping. The first alternative was quickly ruled out because it was not feasiblewith the given time and budget constraints.

The second alternative calls for an evaluation of all commercial applicable packages. Fortu-nately, a timely review article (King 1995) had detail information and critique on the following projectscheduling packages: CA-SuperProject 3.0 for Windows, Microsoft Project 4.0 for Windows, ProjectScheduler 6 for Windows, SureTrack Project Manager for Windows, Texim Project for Windows 2.0,and Time Line for Windows 6.1. The team requested product literature, and obtained copies of thescheduling system (some companies provide a free 30-day evaluation copy, e.g., Microsoft). Thepackages were evaluated on the basis of cost, ease of use, data compatibility, networking capability,PC Windows/Windows NT environment, and modification flexibility. In the end, Microsoft’s Project4.0 emerges as best meeting the criteria except the flexibility in program modification and the numberof simultaneously adjustable resources of the related projects (limited to 80). Incidentally, project 4.0



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is modifiable with the Microsoft Visual Basic programming language.The third alternative “prototyping” (Jenkins and Naumann, 1982) is a well understood and

practiced methodology today. It could be used to build a model of the proposed system and using itto test our understanding of the real requirements. The prototyping process is iterative, evolutionary,and with an emphasis of fast delivery. So, prototyping requires some levels of support by the computeraided software engineering (CASE) tools. A minimum set of components in the CASE is a strongfourth generation language, graphical user interface tools for input and report generation, end-userquery language, and database facility. Today, there are plenty of low-cost and PC-based softwareavailable for prototyping. Examples are Microsoft’s Access, Foxpro, and Visual Basic, Borland’sdBase for Windows, Borland’s Delphi, and Sybase’s PowerBuilder, and many others. These softwarehave strong relational database support, semi-object-oriented programming styles, and a rich set of tools for input forms creation and output report generation.

The evaluation of the three alternatives was also based on time, budget, and company’stechnology architecture grounds. The final development strategy calls for the use of Microsoft’sAccess as the prototyping tool and Microsoft’s Project as the implementation system. This was

because Project was not a prototyping tool. By using Access, the analyst and end-users could build a job scheduling system prototype with databases supporting customized input forms and reportfeatures. The prototype will be used as a basis to customize the Project for the final target system.Another reason for choosing Access and Project was that they fit in the company’s applicationdevelopment architecture. The architecture will be based on Windows NT, SQL Server, and Exchange(a groupware similar to Lotus Notes.) One of the advantages of these software was the built-in OLE(object linking and embedding), OLE automation, ODBC (open database connectivity), and MAPI(massaging application programming interface) tools allowing “seamless” integration betweenapplication systems.

The Project Scope

As the detail of the system requirements unfolds, the company management and the team learnthat a job scheduling system (JSS) could be extremely complex. For example, a JSS had manyinterfaces with subsystems/functions ranging from the client and proposal management to the billingand reports production. Updating a schedule change and optimizing the resource utilization were evenmore difficult. With this understanding, the firm’s management decided to take an evolutionaryapproach by starting development of a small set of core components of the project. The corecomponents were the job order system, the job tracking system, the resource scheduling system, the

job costing system, the experience database management system, and the report generation system.Figure 1 depicts these core components and their related sub-systems.

The Data Model

The forms, reports and computer systems documents collected earlier contain valuable informa-tion for data modeling. Using the entity-relationship (E/R) approach, the analysis of data results in aconceptual database model (Figure 2). The model will be used to establish the database files. A brief explanation of the E/R diagram follows. An account executive could have many clients. A client couldorder many market research jobs. A job could be performed or researched in several ways; thus a jobmay have many sub-jobs (or job versions). Each sub-job must have one study design. Of course, astudy/research design may be used by many sub-jobs. A sub-job consists of many tasks and a task couldbelong to many sub-jobs, thus we have a many-to-many relationship between the sub-job entity and




Figure 1: Sub-systems of the Job Scheduling System




Figure 2: The E/R Diagram for the Job Scheduling System



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completes and sends back the initial job schedule to the level 1, and, notifies the staff for theassignments.

In level three, each staff had a time sheet input screen that contains task assignments, scheduledcompletion dates, and the regular time or overtime entries, etc. Staff executes his/her assignmentsaccording to the staff schedule, and enters the amount of time worked, and posts sick and vacation days,

etc. to the time sheets. Obviously, the time sheet data were interrelated with the departmental staff schedule.

Since data entered at each level were stored in the Access database end-users could now retrievethe job related information more flexibly and timely. The prototype did not have a “resource leveling”component at this time, but it will have once it was converted to the Microsoft Project.

Output Screens

The output screens were mainly reports for users and managers; some examples were:

1) Client and job profile report. It contains the client and the job contract information.2) Job progress report. It provided the status of each task and the percentage of completion of a job.3) Job cost/estimate report. It provided the up-to-date actual job cost data. It could also be used as for

estimating the cost of a proposed project.4) Time report. It was a weekly employee hours worked report for accounting, payroll and staff

schedule updates.5) Job summary report. It was a summery of all job progress and cost status over a specified time by

each client.

Successes and Failures

The prototype was demonstrated and scored well, but did not confirm that the entire developmentprocess was error-free. The following is some successes and failures observed.

Successes

1. The design of the software and hardware architecture.

2. The objectives of the new scheduling system as stated in section 4 were realized; except that it didnot allow for the update of due dates when changes were made.

3. The data model was correctly specified this allows end-users retrieve the information they wantmore easily.

4. The new system will greatly reduce the effort and time spent in updating the schedule when resourceand due dates change.

5. The experience database was established as a by-product of the scheduling system (with somemodifications).




Failures

1. The computerized scheduling system did not completely substitute the manual system because (a)it could be inflexible if tasks required were not in the database, (b) it was difficult to reach anagreement when more than two parties have scheduling conflicts (no conference call facility), and(c) above all, impersonal.

2. The scheduling was not user friendly because the prototype did not have a graphical schedulingfacility such as the Gantt chart.

3. The response time of Access and Project was below expectations.

4. The lack of detail process description in the functional analysis had led to the (three months) delayof the prototype development. An example was the precedence relationship between tasks, a criticalfeature in any scheduling system, but a written master precedence relationship table did not exist.

5. The program (in ACCESS Basic) for the automatic adjustment of time due to changes in due datesand/or resource availability still had bugs. This prevents a lively demonstration of the prototype.

6. The inability of dealing with the “resource leveling” function.

Epilogue and Lessons Learned

The project presented here had well defined objectives. The manual job scheduling system,although developed internally, had been working for many years and was relatively stable. However

the manual system was not a sophisticated scheduling system; it was labor intensive and prone toerrors. So replacing the current system by a computerized scheduling system, the company couldpotentially improve operational efficiency and gain a competitive advantage.

In this project, we have created a prototype. Following the development strategy, the next phasewas to migrate the database to the Microsoft SQL Server, and to customize the Microsoft Projectaccording to the prototype model. A proficient Visual Basic programmer was indispensable in thisphase.

The following were some of the important lessons learned from this project:

1. Defining the project scope. The project had many interfaces with other systems (e.g., accountingsystem; See Fig. 1). This increased the complexity of the project and the development risk. One wayto contain the complexity and the risk would be to start small by limiting the project scope to a fewfunctions and interfaces.

2. Document the process procedure. Although a lot of forms, manuals, reports, and program listingswere received, these were bits and pieces about the job scheduling system in question. How thesebits and pieces work together to support various functions of a company should be clearly spelledout. The process documentation was important in that (a) it could lead to the early discovery of inadequate procedures, and (b) it could augment comprehensive support for latter stages of systemdevelopment.



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3. Avoid project interruption. The scheduling project should not be interrupted by the accountingsystem implementation (which took about nine months) because the team must relearn the systemand the business when they resume their work. This was particularly true when there were twoturnovers in the development team.

4. Select the right technology. Knowing the state and the trend of information technology (hardwareand software) is vital in the design of the hardware and software architecture.

Questions for Discussion

1. Why were the experience database and the automated cost estimating system so important to thecompany?

2. What were the possible applications of the experience database (besides serving as a source of datafor estimating the task time and the cost)?

3. What were the reasons for the top management to launch this project?

4. What were the reasons for selecting Microsoft products in this project?

5. Had the company worked out the detailed procedures of the job scheduling system? Explain.

References

King N. H. (1995). On Time and On Budget, PC Magazine, (April 11) , 165-199.Geoff L. (1993). Object-Oriented GUI Application Development, PTR-Prentice Hall, Inc.March, S. T., & Kim, Y-Gm (1992). Information Resource Management: Integrating the Pieces, DATA-

BASE , (Summer, 1992), 27-37.Milton, J. A. & Naumann, J. D. (1982). Prototyping: The new paradigm for systems development. MIS

Quarterly 6 , 29-44.Bischofberger, W. & Keller, R. (1989). Enhancing the Software Life Cycle by Prototyping. Structured

Programming, (1989), 1, 47-59.Wetherbe, J. C. (1991). Executive Information Requirements: Getting It Right. MIS Quarterly, March, 51-

65.

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