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Systems Analysis I Interface Design ISYS 200 Glenn Booker ISYS 200 Week #7 1 Interface Objectives Key objectives for designing a “good” interface include ISYS 200 Match type of interface to the task Make interface efficient Provide appropriate feedback to users Generate usable queries Improve productivity of knowledge workers Week #7 2 Interface Parts A user interface consists of two parts The presentation language takes computer signals and makes them readable by humans The action language takes human inputs and makes them usable by the computer Together, these parts constitute what we call a user interface ISYS 200 Week #7 3 Types of Interfaces Types of interfaces include ISYS 200 Natural language Question and answer Menus Form-fill Command language Graphical user interface (GUI) And a few other Week #7 4 Natural language Natural language processing is the foundation for being able to ask a database native language (e.g. English) questions www.ask.com handles natural language WWW queries, but is now full of Featured Sponsors Practical information systems have trouble with natural language, due to the vagueness of human languages ISYS 200 Week #7 5 Question and Answer Q&A interfaces are typically used when a limited range of activities and options are needed ISYS 200 Good for inexperienced users Often used for help services (e.g. wizards), and installation routines Week #7 6 Menus Menu interfaces are familiar from almost every Windows and Mac application ISYS 200 Menus are activated based on mouse click or keyboard commands Allows for many command options User is expected to know what kind of task they want to perform More primitive menu systems were based on typing a command letter at each screen Week #7 7 Form-fill Also known as form based or input/output interfaces, this replicates paper forms to provide a familiar environment to the user ISYS 200 Forms appear to be filled out by the user Fields needing data are backlit, colored, or otherwise highlighted Default values and field screens can encourage fast and accurate data entry Poor choice for experienced users Week #7 8 Command language A command language interface is used by typing commands onto a screen Akin to DOS- or UNIX-based command prompts Commands must be learned, and typed correctly ISYS 200 Steep learning curve Very efficient for experienced users Good for very complex applications, e.g. AutoCAD, Mathematica, etc. Week #7 9 Graphical user interface (GUI) GUIs allow direct manipulation of graphic interface objects, providing constant feedback for the user ISYS 200 The objects must provide a conceptual model of the environment depicted, producing a design challenge Users of Web-based GUIs may be completely unknown, so expressing good icons and language are challenging Week #7 10 Other Interfaces Other types of interfaces exist, and are becoming increasingly common ISYS 200 Pointing devices (stylus, tablet PC, touch screen) Voice recognition systems Week #7 11 Interface Type Selection When choosing the type of interface, should consider ISYS 200 The number of users, and their experience level Turnover rate – how long do users stay with the system? Training period should be brief New users should have noticeable productivity Users errors are few and easy to fix Occasional users should relearn system quickly Week #7 12 Dialog Design The dialog between computer and user is critical to the success of any system Want to have ISYS 200 Meaningful communication Minimal user action Standard operation and consistency Week #7 13 Meaningful Communication A system needs to present information clearly to the user (duh!) ISYS 200 Need to format data into recognizable forms Give clear instructions Novice users require more instructions and feedback Help screens or other support tools should be provided Validate inputs to ensure computer understands Week #7 14 Minimal User Action Typing is often the slowest part of a system ISYS 200 Key in codes instead of full words, or select from a dropdown list where possible Only enter new data Format data as user would expect it Provide default values where possible Have system look up names or items, to avoid typing the whole entry Provide keyboard shortcuts Week #7 15 Standard Operation Make the user interface consistent throughout the application ISYS 200 Put common elements in the same place on each screen, and use consistent fonts and layout Use the same function keys or keyboard shortcuts everywhere Use standard shortcuts, like F1 = Help, Esc = exit Use consistent colors and icons everywhere Provide consistent navigation scheme Week #7 16 User Feedback In order for there to be a DIalog between computer and user, the computer must provide good and frequent feedback Feedback generally compares the intended result with an actual result, or tells the user what is expected next ISYS 200 Week #7 17 Types of Feedback There are many types of feedback ISYS 200 Acknowledge input – tell the user when an input has been received by the system Input is valid – tell user that the inputs are in the correct form; it has passed validation Input is invalid – tell user when inputs are not valid; and specifically how to fix them Explain delays – tell the user why there is a delay, so they don’t assume the system crashed Week #7 18 Types of Feedback ISYS 200 Tell when task was completed – tell the user when a request or process has been completed successfully; or conversely Tell when a task wasn’t completed – tell the user if something didn’t complete; and tell them how to redo it or fix the problem Provide additional instructions – provide a way for users to get more information on the current process, or what they can do next Week #7 19 Feedback in Design Use lots of help options ISYS 200 Generic F1 Help Context-sensitive help Balloon help Wizards Customer support phone or email Support forums, chat areas, user groups, etc. Week #7 20 E-Commerce Notes In addition to providing user feedback, many e-commerce web sites also solicit feedback Provide an email link for product comments, help requests, website corrections, etc. Many use one-click navigation ISYS 200 Create using rollover menus, hierarchical links, creating a site map, or using a common navigation bar Week #7 21 Query Types Query structure is outside the scope of this class; typical uses include ISYS 200 Look up a value for a given record Find records matching a condition for an attribute Find when a given attribute has some value Show an entire record Show all records which have a given attribute List attributes that have a given value Week #7 22 Query Methods There are two major methods for querying Query by Example (QBE) is done in Access Structured Query Language (SQL) is used in every major database system ISYS 200 Select the fields of interest, and enter query values Is a click-and-drag way to create queries Uses text commands to specify what tables, attributes, and values are to be evaluated or shown Week #7 23 Web Searching Zillions of resources are available, of varying levels of accuracy and completeness, by searching the WWW Google is a favorite starting point Try www.firstgov.gov for searching state and/or federal government web sites Choose search terms carefully ISYS 200 Spell out part of acronyms Apply logical rules for searches (e.g. AND, OR, exact) Week #7 24 Data Mining Data mining studies past behavior (e.g. sales history) to look for meaningful patterns Often used for marketing or sales, such as targeting an ad campaign Can create a consumer profile based on purchase history Lots of potential privacy issues Data mining tends to be expensive, due to severe computational requirements ISYS 200 Week #7 25