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SYS364. Input Design. Today and next week Agenda. Input Design (Chap.11) Objectives Source Document Design Screen Design Human Factors (Chap.12). GIGO (it’s worse than this) Input Technologies (make a list). Input Design. Pen, Paper & Forms Keyboard, Mouse
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SYS364 Input Design
Today and next week Agenda • Input Design (Chap.11) • Objectives • Source Document Design • Screen Design • Human Factors (Chap.12)
GIGO (it’s worse than this) Input Technologies (make a list) Input Design Pen, Paper & Forms Keyboard, Mouse Screen widgets: check box, radio button, pick lists Touch screen Voice recognition ATMs, Portable devices (e.g. Telxon, PalmPilots) Bar code, MICR, stripe readers OCR, scanner E-pens, drawing tablets E-whiteboard Video capture Biometric devices:thumbprint, retinal scan,face recognition Telephone keypad
Input Design Goal • select the best strategy to get quality data into the system in a timely and accurate manner • i.e. Good & Fast or Fast & Good but almost never Cheap • System boundary is the edge of accessible information
Question • If you are working on a development team creating a tourist information kiosk for airports, what input devices might you consider and why?
Design of System Inputs Textbook, page 407: • Identify devices and mechanisms • List system inputs with data content • Input controls & security • Design and prototype input methods What is wrong with this order? Sequence: 2, 4, 3, 1. Do you agree?
Input Design • define the methods used for data capture, entry and input • Data Capture – record the source data • Data Entry – convert Captured data into computer readable form • Data Input – process Entered data into the Information System
Input Design Objectives • Develop efficient input procedures:Make it easy to do the right things and hard to do the wrong things. Don’t penalize good users. • Reduce input volume • Reduce input errors • With these objectives in mind, does anything change regarding the Kiosk example?
Data Input Techniques • Capture and validate data at source,reduce the information float (time from beginning of Capture to end of Entry) • Reduce input volume (codes, scanners) • Streamline data entryif hard to scan, SKU must be keyed.e.g. poor quality labels, heavy boxes/fixed counter scanner
Data Integration • Retrieve data, avoid reentry.Use PK lookup to get related data. • Integrate systems: • Use EDI, XML, WS-I • Web Services Inspection spec (WS-I) describes what services a business offers and how users can access those services. Allows the components of one application to be used by other applications in different locations via the Web and XML
NEWSWire/400 - 01.25.01 “There's still an immense number of Web sites out there that have a manual back end. They put up a storefront, but the orders get printed somewhere, and a sales-entry person enters them into the real application to be processed. But that manual link can end up being both a business exposure and an expense. Every time you re-key data, you risk having it entered wrong. There are a fair number of cases where the screen tools are linking into e-business, but not performing e-business."-- Janet Krueger, analyst at Andrews Consulting Group
Data Entry Methods • Batch vs On-line data entry • On-line advantages • Immediate validation • Immediate availability of data • Source Data Automation • POS terminals (how long did it take until almost everything had a bar code?) • Data strips on cards for security, access
…list the advantages • Of on-line data entry and/or automated data capture • What are some of the disadvantages? • Information exchange standards • Cost of coding and reading (e.g. barcodes)? • Peak demand? (OLTP throughput) • Inflexible? (alternate input method) • Hardware requirements?
Develop Efficient Input Procedures • Efficient • Use codes • Necessary data only (no black holes) • Retrieve data from system files or calculate from other data • Timely • Seconds multiplied by thousands equals hours. Bottlenecks? Do a stress test. • Manual backup methods?
Reduce Input Errors: control the data • Sequence – complete and together • Existence – is it all there? • Validity – is it a real code? • Data Type – is it the right kind? • Range – allowable values • Reasonableness – sensible valuesNASA’s ozone measurements • Combination – logic • Batch Controls – hash totals
Sequence Existence Data Type Range Reasonableness Validity Combination Batch Controls each day in order # of hours required numeric 0 <= hours <=24 3 <= hours <=12 Employee No. on file Emp.Name matcheson screen and card;O/T rate if hours >40 time card counttotal hourshash total of Emp.No. Timecard Input
Key Tasks in Input Design • List system inputs with data contentexamine the output requirements • Design and prototype input methods • Input controls & security • Identify devices and mechanisms
Source Document Design • Source Document (i.e. paper) • Forms: software that runs on people • Forms used to request and collect input data (i.e. Data Capture) • Also used to trigger or authorize an input action • Provides a record of the original transaction
Why paper is still around: • Familiarmany people are scared of using computersand with good reason :-) • Accessiblenot everyone has access to a computer or network connection when they need it • Exchangeableif you can read, you can exchange it • Portableno power or equipment required • Legiblehigher resolution than screen outputreading a screen is 25% slower than reading print
Source Document Design • Flow follows data capture sequence • Internal vs External Document Quality and appearance • Cost of using a document is greater than the cost of the form itself.
Screen follows Form Form follows Function • Screens should be attractive- not too much stuff at one time • Information displayed in a logical order- follow the form • Screens should be consistent- titles, layout, F keys, buttons, terms • Messages should be specific- help, not error messages • Msgs stay on screen until next user input
Screen follows Form Form follows Function • vertical column alignment – people scan screens – no one reads them • Use special effects sparingly (no blinking!) • Feedback regarding delays are important – e.g. progress bar • Prototype screens with users– usability testing
Screen Design • Data Entry • Process Control • Graphical User Interfaces
Data Entry Screen Design • Restrict user access • Provide a caption for every field • Show sample formats for values • Require an ending keystroke for every field- except for single character fields?- may break rule for high volume data entry • Don’t require use of special characters • Don’t require leading zeroes to fill or trailing zeroes for decimals
Data Entry Screen Design • Display default values and be careful using them! • Display acceptable values whenever possible– e.g. on screen help, pull down lists, check boxes, buttons • Provide method to exit without recording values • Provide opportunity to confirm action –for non-recoverable, low volume transactions only • Provide means to move among fields– cursor defaults to left-right, top-bottom. You can override this. • Design screen layout to match source document • Allow for people to make mistaeks and change their minds • Allow for searching
Process Control Screen Design • Users can enter commands using interactive input • Menu Screens • Prompt Screens
Graphical User Interfaces • Uses graphics such as windows, menus and boxes to allow users to communicate with the system • Double clicking… • Right clicking… • Keyboard shortcuts for expert users • To reap advantage, must have common look and feel
Help • Users do not read manuals (RTFM) • A user reading a manual is a user in deep trouble. • on screen help (labels, prompts, codes) • context sensitive help- single sentence: how to, what for, what is. • AS/400 model: Msg, Cause, Recovery. • detail help -- the online manual
Input Control • Ensure data is correct, complete, secure • Audit trail- transaction logging in computer file- initials, stamps in paper documents- control number references • Workflow- Lotus Notes
Input Control • Computer security- access to programs & files • Physical security- paper, tapes, microfilm, etc.- access and borrowing privileges- offsite storage & records retention
Summary • Input Design • Objectives • Source Document Design • Screen Design