Ch.7 HCI Dr. Prasad

Implementation is so expensive with people time and schedule that in practice it is only done once.

true

Disadvantages of Prototyping

- Users may be unfamiliar with the technique. - If the prototype is "too good," management may think that the project is nearly finished, or that the prototype can be converted into the final product.

Spool Recommends using ___________ __________ as a means to resolve opinion wars.

Local Prototype

Vertical Prototype

Presents only a limited number of features, but the functionality of those features is fully developed. -Example: Prototyping one set of links leading from the homepage to a terminal.

Problems with High-Fidelity Prototypes

- Changes take too long. - One bug can destroy a user test.

Low-Fidelity Prototype

- Do not resemble the final product. Typically called paper prototypes. - Inexpensive in material cost, people time, and schedule time. - No risk of being mistaken for the final product. - Simple and fast to repeat as lessons are learned. - When interface testing of the prototype is complete, implantation can proceed with confidence.

Benefits of Prototyping

- Improves the chances of creating a usable product, since mistakes and omissions are flushed out early in the development process, not after implantation. . - Higher user satisfaction. - Users are good at criticizing an existing system; they are much less able to imagine how specifications would translate into a product. - Prototyping brings users into the process at a much earlier stage.

Advantages of Paper-Based Prototype

- It is easy to build. - It is not necessary to wait for the developer to create a (computer-based) prototype. - It is fast to change (Erasing one link name and writing in another is quicker than rewriting the website code). - It maximizes the number of times the design is refined before anything is committed to implementation. - The lack of polish does not affect user opinion of the prototype

Disadvantages of Low-Fidelity Prototype

- Paper prototypes may need some convention for indicating that an item is "clickable", because users will not be able to watch the cursor change as it passes over a link. - They do not show well to management, because it is not polished. - Low-Fidelity prototypes do not simulate response time accurately.

Evolutionary Prototype

A prototype that is so nearly complete that it constitutes an implementation

Local Prototype

Also called a scenario. -Models a very small part of a site. -It is usually a stand-alone model that's not connected with the rest of the pages and typically has a very short life span.

Stages of development that occur after user/task analysis

Design, One or more prototypes each followed by testing and redesign, Implementation, Site goes live

Revolutionary or Throwaway Prototype

Developers still use the prototype to guide their implementation, but the prototype itself is discarded

Global Prototype

Has breadth and depth. -It is a prototype of the entire site, and gives users the opportunity to get a good appreciation of the look and feel of the entire site.

Horizontal Prototype

Has little depth of functionality but is broad in terms of the number of features it presents. - Horizontal prototypes are useful for presenting an overview or the "big picture" perspective of a site's "look"

High Fidelity Prototype

closely resemble the final product, create the danger of raising false expectations in management