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