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Main page   /   Theory   /   Satisfaction



ISO-9241 standard defines Satisfaction with the product as �comfort and relevance of application�.

In contrast to Efficacy and Productivity, where we observe and evaluate the user�s actions, Satisfaction aims at subjective thoughts of the user.

There are two widespread methods of Satisfaction measurement.

Method 1: Satisfaction is measured through a formalized questionnaires featuring satisfaction scales.

Each questionnaire contains a number of statements reflecting subjective user�s opinion on interaction with the product. For example, �I like the way interface looks� or �I believe the product to be too complicated�.

Each scale features between 3 and 11 answers. Here is the example of a 5-point scale:

No Rather not Neutral Rather yes Yes

Weight � numeric value of the satisfaction coefficient, which depends on the answer.
Weight for a 5-point scale can be estimated differently, e.g. from -2 to +2, from 1 to 5 or from 0 to 4.

The questions and statements concerning the product might sound both positive and negative.

A positive question with weight driven by answers:

No Rather not Neutral Rather yes Yes
0 1 2 3 4

Example: �I am satisfied with the speed of this product�

A negative question with weight driven by answers:

No Rather not Neutral Rather yes Yes
4 3 2 1 0

Example: �I often made mistake while doing tasks�

R � the number of respondents
Q+ � the number of positive questions featuring in the questionnaire
Q- � the number of negative questions
pij+ � weight for the answer to a positive question (0-4) for i-scenario and j-respondent
pij- � weight for the answer to a negative question (4-0) for i-scenario and j-respondent

the average satisfaction (S) is estimated through the following formula:

Average satisfaction (10)

Statistical error of Satisfaction:

Error of satisfaction (11)

Total satisfaction with the product:

Total satisfaction (12)

Satisfaction questionnaires applied for our tests:

  • SUS (System Usability Scale) suggested by the Digital Equipment Corporation � 1986
    (10 questions, a 5-point scale)

  • QUIS (Questionnaire for User Interaction Satisfaction) suggested by the Human-Computer Interaction Lab (HCIL) at University of Maryland at College Park � 1990
    (24 questions, a 10+1 point scale)

  • SUMI (Software Usability Measurement Inventory) suggested by the Human Factors Research Group � 1993
    (50 questions, a 3-point scale)

  • CSUQ (Computer System Usability Questionnaire) suggested by IBM � 1995
    (19 questions, a 7+1 point scale)

Besides, we apply ISO-20282 standard ("Easy of operation of everyday products: Test method for walk-up-and-use products"), which expands ISO-9241 standard � applicable for products aimed at day-to-day use. This standard presupposes application of extra Smiley Scale � Kunin, 1955.

The Smiley Scale method. The respondent is to choose one smiley in five to reflect his/her satisfaction with a certain action:

Smiley scale

Weight coefficients range from -2 to +2.

Method 2. The Word Method enables to uncover subjective associations generated by the product.

One of the Word lists versions comprises 118 adjectives with positive and negative connotation. � 2002 Microsoft Corporation. All rights reserved.

Each user is to highlight words reflecting his/her interaction with the product. The words feature in alphabetical order and negative ones are mixed with the positive.

The aggregated results enable to draw a diagram reflecting the general impression of users confronted with the product. Fr convenience purposes positive associations are highlighted in green and negative � in red. The Associations diagram is aligned in accordance with the number of respondents.

Associations diagram for 11 respondents:

Satisfaction diagram word test

R � number of respondents
A+j � number of positive words-associations provided by j-respondent
A-j � number of negative words-associations provided by j-respondent

The total Associate Satisfaction is estimated through the following formula:

Common satisfaction (13)

Further: Methods

Users and Goals | Effectiveness | Efficiency | Satisfaction | Methods