User Interfaces Interface IS the system UI an important determinant of success of MSS –Execution time –System versatility –Learning time for users, end.

User Interfaces• Interface IS the system• UI an important determinant of success of MSS

– Execution time– System versatility– Learning time for users, end users with differing competency– Ease of recall, concentration level required of end users,

fatigue, information overload– End-user errors

• Subset of Human Computer Interaction• People, computer technology, and the ways they interact

User Interface Design

Components• Action Language• Display/presentation language• Knowledge• Dialog

Modes of communication• metaphor• mental model• navigation of model• look

Action language

• Format of input used by decision makers– way decision makers request info., invoke models,

perform sensitivity analysis, request mail, etc.

• menu format• question answer format• command language format• input/output structured format• free-form natural language

Menus• Display lists of alternatives for DM to select

• inexperienced users, users who use DSS infrequently

• not the optimal action language for experienced users - sequence of keystrokes/menu-choices

• understandability of menus– naming according to DM language– logical listing of options (alphabetical, numeric, frequency of

use, pre-selected most common choice)– grouping commands and objects – menus nested in logical sequence

Independent command and object menus

Combined command and object

Nested menu structure

Question/Answer format

Command Language format

• power users

• complete control

(nightmare for inexperienced users)

I/O Structured format

• not a primary action language for DSS• repeated, structured, manual process

Display or presentation Language

• wide categories of info.

• uncluttered desktop• use of icons

Example: Court DSS

• To enable judge to see entire perspective of a case

– infractions that a defendant may have been involved in– prior criminal history– specific complaint in question– defendant’s socio-economic, health data

• drugs used, treatment, with whom the defendant lives, where, how long

– court appearance history, non-attendance, why– judge’s comments– etc.

Display/Presentation: representations

• Metri-glyphs– smiling face: sales target met

– larger smiley: larger sales

– smile represents profit level, eyes represent dividend level

– closed eye: no dividend, size of eye: size of dividend !!!!

• Map with colors depicting different sales levels• graphs, actual numbers• animation, video

• simulation of bank with number of clerks, types of services handled by each clerk, number of queues, - impact of factors on queue length

Graphs and bias

• 5000 vs 3000 (std. deviation: 2000?)• Scaling of graphs

– Sales (0-200), Sales(0-1000)

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Mode of communication• Mental models

– desktop for organizing office work

– operating room tasks?

– Understanding how users think about their work

• Metaphors– substitution of symbols for information or procedures– should convey intended meaning accurately, intuitively

Mode of communication

• Navigation– movement among the data and functions– quick access, easy understanding

• Look and feel– corporate culture, individual preferences– cultural factors

• significance of colors, size of images in video-conferencing, linear vs. alternate menu formats, etc.

Some user-interface design issues

Prototyping

• “Low-fidelity” prototyping– designers and users design screens together using paper

template items

• high fidelity prototyping

• User interface tools