1. To Enter or Not Enter: That Is the Question
"I've just taken on the presidency of Elsinore Industries," says Rose N. Krantz. "We're actually part of a small cottage industry that manufactures toy villages for children seven years old and up. Our tiny hamlets consist of various kits that will build what chil¬dren want from interlocking plastic cubes, essentials such as city hall, the police station, the gas station, and a hot dog stand. Each kit has a unique part number from 200 to 800, but not every number is used. The wholesale prices vary from $54.95 for the city ball to $1.79 for a hot dog stand.
"I've been melancholy over what I've found out since signing on at Elsinore. 'Something is rotten' here, to quote a famous play¬wright In fact, the invoicing system was so out of control that I've been working around the clock with our bookkeeper, Gilda Stern," Krantz soliloquizes.
"I would like you to help straighten things out," Rose con¬tinues. 'We ship to 12 distribution warehouses around the coun¬ty. Each invoice we write out includes the warehouse number, 1 through 12, its street address, and the U.S. postal code (zip code). We also put on each invoice the date we fill the order, code numbers for the hamlet kits they order, a description of each kit, the price per item, and the quantity of each kit ordered. Of course, we also include the subtotals of kit charges, shipping charges, and the total that the warehouse owes us. No sales tax is added, because-they resell what we send them to toy stores in all 50 states. I want you to help us design a computerized order entry system that will be part of the invoicing system for Elsinore Industries."
For your design of a data entry system for Elsinore, take into consideration all the objectives for data entry discussed throughout this chapter. Draw any displays necessary to illus¬trate your design. How can you make the order entry system efficient? Respond in a paragraph. Specify what data can be stored and retrieved and what data must be entered anew for each order. How can unnecessary work be avoided? Write a paragraph to explain why the system you propose is more effi¬cient than the old one. How can data accuracy be ensured? List three strategies that will work with the type of data that are being entered for Elsinore Industries.
Errors cannot be ruled out entirely, and the critical importance of catching errors during input, prior to processing and storage, cannot be overemphasized. The snarl of problems cre¬ated by incorrect input can be a nightmare, not the least of which is that many problems take a long time to surface. The systems analyst must assume that errors in data will occur and must work with users to design input validation tests to prevent erroneous data from being processed and stored, because initial errors that go undiscovered for long periods are expensive and time-consuming to correct.
You cannot imagine everything that will go awry with input, but you must cover the kinds of errors that give rise to the largest percentage of problems. A summary of potential problems that must be considered when validating input is given in Figure 1.
FIGURE 1
Validating input is important to ensure that most potential problems with data are eliminated early.
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This Type of Validation
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Can Prevent These Problems
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Validating Input Transactions
Validating Input Data
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Submitting the wrong data
Data submitted by an unauthorized person
Asking the system to perform an unacceptable function
Missing data
Incorrect field length
Data have unacceptable composition Data are out of range
Data are invalid
Data do not match with stored data
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2. Waiting to Be Fed
Yeah, we were sold a package all right. This one right here. Don't get me wrong, it gets the work done. We just dontt know when."
You are tailing with Owen In, who is telling you about the sales unit's recent purchase of new software for its networked PCs that allows the input of sales data for each of its 16 salespeople, provides output showing comparison data for them, and projects future sales based on past sales records.
"We've had some odd experiences with this program, though," Owen continues. "It seems slow orsomething. For instance, we're never sure when it's done. I type in &command to get a file and nothing happens. About half a minute later, if I'm lucky, the dis¬play I want might come up, but I'm never sure. If I ask it to save sales data, I just get a whining sound. If it works, I'm returned to where I was before. If it doesn't save data, I'm still returned to where I was before. It's confusing, and I never know what to do. There's nothing on the display screen that tells me what to do next. See the little manual that came with it? It's dog-eared because we have to keep thumbing through it trying to figure out what to do next. Or we go online to try to get some help, but their technical assistance is just about nonexistent It takes way too much time, too."
Based on what you've heard in the interview take this opportunity to supplement the software by designing some onscreen feedback for Owen and his sales team. The feed¬back should address all of Owen's concerns, and follow the guidelines for giving feedback to users, and the guidelines for designing good displays. Draw a prototype of the displays you think are necessary to address the problems Owen lists.
7. Use radio buttons and drop-down lists to control displays of new web pages or to change Web forms. For example, when a radio button is clicked, a drop-down list may change to reflect the radio button choice. A radio button may be clicked, and a form may change according to the choice. A drop-down list may change or a radio button may be clicked to move to a new web page. Drop-down lists are often provided on a web page for quick navigation; selecting a new web page from the drop-down list takes the viewer to that page.
8. Provide cursor control for Web forms and other displays so that the cursor moves to the next field when the right number of characters has been tittered. An example would be when a user enters an area code for a U.S. telephone number, and, follow¬ing the entry of three characters, the cursor moves to the local phone number field. Entering software registration key codes is another example. The codes are often in groups of four or five letters and, when the first field is filled, the cursor moves to the next field and so on. The analyst should examine every field to see whether automatic cursor control should occur.
Any combination of these eight approaches can help the analyst decrease the number of keystrokes required by the user, thereby speeding up data entry and minim/ring errors.
Standard Operation and Consistency
A system should be consistent throughout its different displays and in the mechanisms for con¬trolling the operation of the displays throughout different applications. Consistency makes it easier for users to learn bow to use new portions of the system once they are familiar with one component You can achieve consistency by:
1. Locating titles, date, time, and operator and feedback messages in the same places on all displays
2. Exiting each program by using the same key or menu option
3. Canceling a transaction in a consistent way, such as using the Esc key
4. Obtaining help in a standardized way, such as using a function key
5. Standardizing the colors used for all displays or web pages
6. Standardizing the use of icons for similar operations when using a graphical user interface
7. Using consistent terminology in a display screen or website
8. Providing a consistent way to navigate through the dialog
9. Using consistent font alignment, size, and color on web pages
Feedback for Users
All systems require feedback to monitor and change behavior. Feedback usually compares current behavior with predetermined goals and gives back information describing the gap between actual and intended performance.
Because humans themselves are complex systems, they require feedback from others to meet psychological and cognitive processing needs discussed earlier in this chapter. Feedback also increases human confidence. How much feedback is required is an individual characteristic.
When users interface with machines, they still need feedback about how their work is progressing. As designers of user interfaces, systems analysts need to be aware of the human need for feedback and build it into the system. In addition to text messages, icons can often be used. For example, displaying an hourglass while the system is processing encourages the user to wait a while rather than repeatedly pressing keys to get a response.
Types of Feedback
Feedback to a user from a system is necessary in seven distinct situations. Feedback that is ill timed.or too plentiful is not helpful because humans possess a limited capacity to process information. Websites should display a status message or some other way of notifying the user that the site is responding and that input is either correct or in need of further information. Figure 14.10 provides some examples for each type of feedback.
ACKNOWLEDGING ACCEPTANCE OF INPUT. The first situation in which users need feedback is to learn that the computer has accepted the input. For example, when a user enters a name on a line, the computer provides feedback to the user by advancing the cursor one character at a time when the letters are entered correctly. A Web example would be a web page displaying the message "Your payment has been processed. Your confirmation number is 1234567. Thank you for using our services."
RECOGNIZING THAT INPUT IS IN THE CORRECT FORM. Users need feedback to tell them that the input is in the correct form. For example, a user inputs a command, and the feedback states "READY" as the program progresses to a new point_ A poor example of feedback that tells the user that input is in the correct form is the message "INPUT OK," because that message takes extra space, is cryptic, and does nothing to encourage the input of more data. When placing an order on the Web or making a payment, a confirmation page often displays,
FIGURE 2
Feedback can take many forms.
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Type of Feedback
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Sample Feedback Response
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Acknowledging acceptance of input
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"Your payment has been processed."
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Recognizing that input is in the correct form
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An LED-like display turns from red to green
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Notifying that input is not in the correct form
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"The telephone number should be separated by dashes (-)"
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Explaining a delay in the processing
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An hourglass or a rotating circle
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Acknowledging that a request is completed
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"You successfully renewed your membership. Thank you."
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Notifying that a request was not completed
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"Your attempt was not successful. Please try at a later lime."
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Offering the user more detailed feedback
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"Your credit card was not charged. You must enter a valid expiry date. Press help if you need More information."
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