Designing the System Output Chapter 11 Designing the System Output

Learning Objectives Understand the process of designing high quality and effective system output Identify the basic characteristics of high quality system output Discuss control strategies for system output

Learning Objectives Identify and discuss the various categories of output, media, and output technology Understand ways in which unintentional bias can be introduced into system output Identify and discuss available backup and retention strategies for data recovery

Introduction Users of an IS need output to accomplish their assigned tasks. The overall satisfaction with a system is often measured by the quality of its output.

Designing System Output Objective of Output To create output that presents the desired information to the end user in an understandable and usable fashion

Output Characteristics Purpose What is the intended use or purpose of the output? The purpose of the output may dictate the order or sequence of the various data elements contained within it.

Output Characteristics Recipient Who will be the primary users of the output? The intended recipients of the output should be involved in the design and approval of each system output relevant to their assigned tasks.

Output Characteristics Frequency How often will the output need to be generated? Minimizing the time between the request for the output and the receipt of the output

Output Characteristics Distribution Where will the output be used? Output distribution is becoming less important due to the increased sophistication of client-server environments and local computer peripherals.

Output Characteristics Human-machine Boundary The point where an end user interacts with the system through the exchange of data or information

Figure 11-1. Human – Machine Boundary for Employee Payroll System 1.0 Create Weekly Payroll Record Employee Data File S1 Employee Employee Tax Form Payroll Data File S2 Accounting Department 2.1 Compute Gross Pay 2.3 Check 2.2 Net 3.2 Print Summary 3.1 Sort Records by 4.2 Tax Form 4.1 Calculate Deductions Employee Paycheck Employee Payroll Time Sheet Employee Record Gross Pay Data Net Pay Hours Worked Payroll Record Sorted Records Payroll Report Figure 11-1. Human – Machine Boundary for Employee Payroll System

Output Characteristics Data Sources What information must be delivered by the output? No source data, no output

Output Characteristics Media In what form will the output be delivered? If a given output must be generated using more than one primary media, additional design constraints may be encountered.

Output Characteristics Format How will the content of the output be displayed and formatted? Tabular Zoned Narrative Graphical

Figure 11-2. Combination Approach to Screen-Based Output

Output Characteristics Control What controls are necessary to limit access to the output? Distributed control Division of labor Completeness control

Table 11-1. Output Design Issues to be Addressed

 Table 11-2. Common Design Guidelines for Output

Table 11-3. Common Completeness Controls for System Output

Types of Output External Output Leave the boundary of the system and serve to either confirm a system action to the recipient or to trigger an action on the part of a recipient Turnaround Document

Types of Output Internal Output Output that normally stays within the system boundary and is used to support the organizational responsibilities and activities of the end users

Internal output Detail Report To present data or information with only a minimum amount of filtering Historical lists of transactions A list of customers sorted by zip code A list of paychecks for a given period

Internal output Summary report To allow users to review information in a filtered or categorized form Month-to-date or year-to-date sales by product category

Internal output Exception report An internal output that contains filtered information intended to report events or transactions that require special attention Overdue customer accounts A list of items reach reorder point

Media Type and Output Technology Hard Copy Still the most common output media Impact technology Non-impact technology

Media Type and Output Technology Screen Output Can be viewed from any location Offers real-time editing and modification Reduces storage costs Does not require long-term storage

Media Type and Output Technology Audio and Video Output Rich in the communication of information Provides high quality interaction with users and customers Speech synthesis and recognition

Figure 11-4. Screenshot from Video Editing Software

Media Type and Output Technology COM Output Computer output microfilm or microfiche Decreasing in popularity due to advancement in digital scanning and storage technologies

Media Type and Output Technology Robotic Output Used as a vehicle for complex output intended to automate production, manufacturing, distribution, and applications requiring precise handling of physical component Microsurgery and minimally invasive surgery

Figure 11-5. Robotic Output Devices

Table 11-4. Common Output Media and Technologies

Output Bias Issues Range or Value Limits Sorting or Sequence Graphics

Output Bias Issues Range and Value Limits Inappropriate limits on displayed values Can introduce inaccuracies in information contained in the output. Ranges that are set too low, too high, too narrow, or too wide Can result in exception reports that are either of little use or introduce unnecessary biases into the decision process.

Output Bias Issues Sorting and Sequence Bias Common methods Alphabetical Chronological Size Cost

Figure 11-6. Example of Graphical Scaling Bias

Output Bias Issues Graphical Bias Inappropriate scaling can introduce an unintended bias into graphical information.

Backup and Recovery Back files of an IS are internal outputs, too. 50 percent of end users suffer some form of data loss each year. Over half of the world's commercial enterprise with no backup procedures could go bankrupt with 6 months following a catastrophic loss of data.

Cost of Data Loss $50,000 per Mb to re-create $18,000 per hour in downtime cost for PC LANs $75,000 per hour in downtime cost for UNIX network $17,000 to re-create 20 Mb of sales and marketing data $19,000 to re-create 20 Mb of account data $98,000 to re-create 20 Mb of engineering data

Backup and Recovery Disaster recovery Plan A comprehensive statement of consistent actions to be taken before, during, and after a disaster

Data Backup and Retention Strategies Incremental backup Establish a repetitive cycle that begins with a full backup of all data files and continues through a series of incremental backups

Table 11-5. Incremental Data Backup Strategy

Data Backup and Retention Strategies Differential backup A variation of the incremental backup Based on the backup of all modified files since the previous full backup

Data Backup and Retention Strategies Generational backup Use a system of tape rotation via three storage sets. Set One: “grandfather” Set Two: “father” Set Three: “son”

Table 11-6. Generation Data Backup and Retention Strategy

Data Backup and Retention Strategies On-line backup system Procedure Automatically detect files on an organization’s computer network requiring backup. Encrypt those files for security. Compress the encrypted files. Transmit the data through high-speed network. The amount of work to fully protect the data is greatly reduced.

Chapter Summary The goal of IS is to deliver high quality and relevant information to the end users of the system. The specification of the complete scope of the outputs for a system is critical.

Chapter 11 End of Chapter