IT 214 | User Experience Design Lecture 4: Design Rules 2 - Flexibility Principles

This flashcard set covers the key principles of flexibility in user experience design as detailed in the lecture transcript, including dialog initiative, multi-threading, task migratability, substitutivity, and customizability.

Learnability

The ease with which new users can begin effective interaction and achieve maximal performance.

Flexibility

The multiplicity of ways the user and system exchange information.

Robustness

The level of support provided to the user in determining successful achievement and assessment of goals.

Dialog Initiative

Refers to who initiates or controls the dialog flow between the user and the system.

System pre-emptive

A type of dialog initiative where the system initiates all dialogs and the user responds to requests; it is often used for safety reasons to prevent serious damage.

User pre-emptive

A type of dialog initiative where the user is entirely free to initiate any action towards the system, granting total access without constraints.

Multi-threading

The ability of the system to support user interaction for more than one task at a time.

Concurrent multi-threading

Allows simultaneous communication of information pertaining to separate tasks, such as editing text while hearing an audible beep for a new email.

Interleaved multi-threading

Permits a temporal overlap between separate tasks but stipulates that at any given instant the dialog is restricted to a single task, such as overlapping windows for different tasks.

Task Migratability

Measures how easily a certain task can be moved (migrated) between the user and the system, allowing control to be passed or shared.

Substitutivity

The principle of allowing equivalent values of input and output to be substituted for each other.

Input substitutivity

Allows the user to choose the best form of data entry for their needs, such as entering margins in $\text{inches}$ or $\text{centimeters}$, to reduce cognitive effort.

Output substitutivity

Allows the system to show the same internal state in different, equivalent forms, such as representing temperature as digits or a graph.

Customizability

The modifiability of the User Interface (UI) by either the user (adaptability) or the system (adaptivity).

Adaptability

A type of customizability where the user explicitly adjusts the form of input and output, such as changing the position of icons or text.

Adaptivity

A type of customizability where the system automatically adjusts the interface based on user expertise or observed repetition of task sequences.