N341 Analysis Chapter 3

Overview

WD1 discussed and presented an example for determining the goal of the Web site and getting to know the site users. Analysis involves identifying the user tasks and a recognizable organization. The goal of analysis is to provide insight into the Web site structure (which page links to another to achieve the desired workflow) and page organization (how to organize pages to fit the user's mental model). 

Much of the following discussion is based on the project, the stock trading Web site.

Task Analysis

Goals - The first step is to determine the user goals, what do they hope to achieve in using your Web site. 

Exercise 1 What is the user goal of a stock trading Web site?

Tasks are the mechanisms people use to accomplish goals. Such things as registering for a class is a task used to accomplish in completing a degree.

Exercise 2 What are two tasks for stock trading?

Actions are subcomponents of tasks. Tasks are high-level descriptions, while actions are the individual steps that comprise a task. 

Exercise 3 Break down one  task into actions (steps).

There are a number of common approaches to task analysis. A few are:

• Workflow analysis - Describes how work gets done, provide the big picture or overview.

  Consider how the goal of buying an airline ticket is achieved below.

  Most of these steps could be broken down further, such as number 3 could include checking a calendar, determining the airport, etc.

  1. Arrives at Orbitz
  2. Selects Air Fare
  3. Enters departure airport and date, destination airport and return date, and number of passengers.
  4. Selects a flight from list.
  5. Enters personal passenger information.
  6. Verifies flight and passenger information correct. 
  7. Submits credit card information.
  8. Receives ticket purchase confirmation.

  Alternatively, a flowchart can express the same information.

  

  The advantage of the list is that it can be easily changed as compared to the flowchart.

  A disadvantage of the list is that it does not illustrate decisions very well.

Exercise 4 List a part of the workflow for a new user to open an account and purchase a stock. Include the receptionist and stock broker.

• Job analysis - Focus on a what single person does in a day, week, etc. through an interview and observation. Produces a list of the tasks person performs. This differs from Workflow Analysis which is concerned with the steps required to complete a task; Job Analysis is concerned with what is involved in specific job. This is more appropriate when the user interface is part of a system for employees used to complete their work. For example, the stock broker has certain manual tasks that are to be computerized.
  1. Create client portfolio.
  2. Update current portfolio values.

Exercise 5 Give the job analysis for a new user, that is, to open an account and purchase a stock.

• Task list - Reduces the granularity of job analysis to the details of a single task. For example:
  •  locate the airport in the the destination city

Exercise 6 Give some of the task details for a new user to open an account.

• Task sequences - Establish an order in which the tasks take place. May be as simple as ordering the items in the task list, for existing tasks can be determined by watching users. There may be other sequences that achieve the same result. With four tasks there are 24 possible sequences, users should be able to choose any valid sequence.

Purchasing an airline ticket seems to have only one path but, suppose you'd like a hotel and car at the destination or multi-stop ticket.

Exercise 7 Can the task details for a new user to open an account be arranged several different valid sequences? What is the most logical? For example, when should credit card information be provided?

• Task hierarchies - Documents the the components of a task broken down into subtasks.

  The following breaks down into a hierarchy of tasks and subtasks the user task of buying an airline ticket. The task hierarchy provides insight for page links that define the web site structure. 

Exercise 8 Draw the task hierarchy to perform the top-level user task of opening an account.

• Procedural analysis - Shows individual steps and decisions that a user goes through in carrying out a task. At right is a partial procedural analysis for purchasing an airline ticket.

Exercise 9 Give a procedural analysis of the user task of opening an account.

Usability Specifications

Answers question of how good does the user interface need to be; these fall into two categories:

1. Performance measures - Directly observable and quantifiable such as time to complete task and number of errors.

   For example: Ticket purchases should be completed in 15 minutes with an error rate of 1%.
    

2. Preference measures - Based on user opinion about the user interface, not directly observable. Include such opinions as ease of use and appearance. Typical questionnaire measures opinion scaled from strongly agree to strongly disagree to some aspect of the user interface.

For example: Is the placement and purpose of the Submit button obvious?