What Variables Affect Web Credibility

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What Variables Affect Web Credibility?

• A Report of Ongoing Research from Stanfords
  Persuasive Technology Lab
• BJ Fogg (bjfogg_at_stanford.edu)

First presented at CSLIs Industrial Affiliate
Conference Stanford University, November 11, 1999
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Overview

• Level 1 A First Look at Credibility
• definitions, basic issues
• Level 2 Four Types of Credibility
• different kinds of credibility
• Level 3 Web Site Variables
• web elements and a framework
• Level 4 Variables Outside the Web
• individuals, goals, and contexts
• Level 5 Three Moving Targets
• people, experience levels, and technology

Plus two studies
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Level 1 A First Look at Credibility

• Level 1 A First Look at Credibility
• definitions, basic issues
• Level 2 Four Types of Credibility
• different kinds of credibility
• Level 3 Web Site Variables
• web elements and a framework
• Level 4 Variables Outside the Web
• individuals, goals, and contexts
• Level 5 Three Moving Targets
• people, experience levels, and technology

Plus two studies
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Why does Web credibility matter?
Answer 1
Creators
Web sites with optimal levels of credibility
Consumers
PT Lab
What to believe on the web (aka information
quality)
A key factor in Web-based persuasion
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Why does Web credibility matter?
Answer 2
Web has least credible info of any medium
Web has most credible info of any medium
Web presence is vital for many companies
The Web is not going away any time soon
Web standards are taking shape now
Big money is at stake
Few have studied this (publicly)
Explosion of Web-based info services
Web users are vulnerable
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What is credibility?

• Believability
• or
• A perception based on two factors . . .

truthful
experienced
unbiased
intelligent

trustworthiness
expertise
powerful
good
honest
knowledgeable
Some studies have shown three or more factors
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Highly credible web sites have. . .

• High levels of perceived trustworthiness and
  expertise

perceived trustworthiness
perceived expertise
perceived credibility
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One factor can damage credibility

perceived lack of trustworthiness
perceived expertise
perceived lack of credibility

perceived trustworthiness
perceived lack of expertise
perceived lack of credibility
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Some semantic issues

• Credibility and Trust
• Similar terms but not the same construct
• Phrases that refer to credibility
• trust the information
• accept the advice
• believe the output

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Expertise Trustworthiness
In these examples, what elements convey
expertise? What elements convey trustworthiness?
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Expertise Trustworthiness
In these examples, what elements convey
expertise? What elements convey trustworthiness?
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Level 2 Four Types of Credibility

• Level 1 A First Look at Credibility
• definitions, basic issues
• Level 2 Four Types of Credibility
• different kinds of credibility
• Level 3 Web Site Variables
• web elements and a framework
• Level 4 Variables Outside the Web
• individuals, goals, and contexts
• Level 5 Three Moving Targets
• people, experience levels, and technology

Plus two studies
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Four Types of Credibility

• 1. Presumed Credibility
• 2. Reputed Credibility
• 3. Surface Credibility
• 4. Experienced Credibility
• Its helpful to distinguish different types of
  credibility.
• But you wont find these distinctions in the
  psychology literature.

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1. Presumed Credibility

• We believe because of general assumptions we hold.

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1. Presumed Credibility

• We believe because of general assumptions we
  hold.
• Examples . . .

Increases credibility
Decreases credibility
Site has AOL domain name Very few hits on web
counter Info on the site is rarely updated
Domain name has .org Lots of hits on web
counter Info on the site is constantly updated
These are working hypotheses. To date, weve
studied only some of these variables.
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2. Reputed credibility

• We believe because of a reference from a third
  party.

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2. Reputed credibility

• We believe because of a reference from a third
  party.
• Examples . . .

Increases credibility
Decreases credibility
Your friend said the site was horrible. The
newspaper said the site was down for three
days. A political group you dont like endorses
the site.
Your medical doctor referred you to this Web
site. The site won an award. An authoritative Web
site linked to this site.
These are working hypotheses. To date, weve
studied only some of these variables.
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3. Surface credibility

• We believe because of what we find on simple
  inspection.

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3. Surface credibility

• We believe because of what we find on simple
  inspection.
• Examples . . .

Increases credibility
Decreases credibility
Site looks confusing. The organization has no
presence outside the Web. The site uses many
animated features.
Site looks professional. Site is from an
organization you recognize. You see that articles
have citations.
These are working hypotheses. To date, weve
studied only some of these variables.
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4. Experienced credibility

• We believe because of past experience with site.

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4. Experienced credibility

• We believe because of past experience with site.
• Examples . . .

Increases credibility
Decreases credibility
The site has a broken link. The site takes a long
time to download each page. Youve seen factual
errors on the site.
You get a quick response to a customer service
question. You can navigate the site
easily. Youve found the content to be fair and
balanced.
These are working hypotheses. To date, weve
studied only some of these variables.
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Why this framework is helpful

• Provides a set of terms for discussion
• Enhances both research design
• Asking better questions
• Seeing more possibilities

Presumed Credibility
Reputed Credibility
Surface Credibility
Experienced Credibility
Trustworthiness
Expertise
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Why this framework is helpful

• Provides a set of terms for discussion
• Enhances both research design
• Asking better questions
• Seeing more possibilities

Presumed Credibility
Reputed Credibility
Surface Credibility
Experienced Credibility
Trustworthiness
?
Expertise
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Four Types of Credibility

• Presumed
• Reputed
• Surface
• Experienced

Can you identify the different types of
credibility in these examples?
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Four Types of Credibility

• Presumed
• Reputed
• Surface
• Experienced

Can you identify the different types of
credibility in these examples?
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Level 3 Web Site Variables

• Level 1 A First Look at Credibility
• definitions, basic issues
• Level 2 Four Types of Credibility
• different kinds of credibility
• Level 3 Web Site Variables
• web elements and a framework
• Level 4 Variables Outside the Web
• individuals, goals, and contexts
• Level 5 Three Moving Targets
• people, experience levels, and technology

Plus two studies
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Level 3 Web Site Variables

• How to contain the many elements of a Web site?
• Weve created some frameworks
• Ill talk about one.
• See www.webcredibility.org for others.

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Framework for Web Site Elements

• Web Site Provider
• Person or organization that offers the site
• e.g., IBM, Kodak, Amazon
• Web Site Content
• Information
• Functionality
• Web site Design
• Aesthetic design
• Information design
• Technical design

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Web Credibility Grid
Presumed Credibility
Reputed Credibility
Surface Credibility
Experienced Credibility
Web Site Provider
Web Site Content

• information
• functionality

Web Site Design

• aesthetic
• information
• technical

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Web Credibility Grid
Examples of elements that increase credibility
Presumed Credibility
Reputed Credibility
Surface Credibility
Experienced Credibility
The provider is a nonprofit organization.
Users are familiar with the provider outside of
the Web context.
The provider is recognized as an expert by others.
Users with questions receive quick and helpful
answers.
Web Site Provider
The site has ads from reputable companies.
The sites content has always been accurate and
unbiased.
The site appears to have lots of relevant
information.
The content has been approved by an outside
agency.
Web Site Content

• information
• functionality

The site was created by an outside design firm.
The site is easy to navigate.
The site won an award for technical achievement.
The site has a pleasing visual design.
Web Site Design

• aesthetic
• information
• technical

These are working hypotheses. To date, weve
studied only some of these variables.
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Web Credibility Grid
Examples of elements that decrease credibility
Presumed Credibility
Reputed Credibility
Surface Credibility
Experienced Credibility
The site tries to recruit advertisers but has
none so far.
The sites URL does not match the providers name.
The provider was sued for patent infringement and
lost.
The site doesnt give contact information
anywhere.
Web Site Provider
The site shows only a few hits on their web
counter.
The site has typographical errors.
The site seems to have more ads than information.
The content got bad reviews from an outside
agency.
Web Site Content

• information
• functionality

The site has no security protocols for
transactions.
The site has links to pages that no longer exist.

The site is reported to have copied the design of
another site.
The text font is either too large or small to
read comfortably.
Web Site Design

• aesthetic
• information
• technical

These are working hypotheses. To date, weve
studied only some of these variables.
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Small Survey on Web Credibility

• Pilot study on 45 variables
• Questionnaire, n 25, with Nina Kim
• Purpose To select variables for experiment
• Sample question
• The Web site lists an author for each article.
• -3 -2 -1 0 1 2 3
• much much
• less more
• credible credible

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Survey results were interesting
Was referred to you by a good friend
Provides quick response to a customer service
question
Lists a physical address for the page sponsor
Represents a company or organization you recognize
Is easy to navigate
Presents information that may help its competitors
more credible
Lists an author for each article
Contains a link to a site you trust
Has .org in the domain
Contains an ad for IBM
Has .com in the domain
Charges a monthly access fee
Contains animation
Was created with PageMill or FrontPage software
less credible
Contains a typographical error
Makes it difficult to distinguish ads from content
Contains broken links
Contains misleading ads
Contains many spelling and grammatical errors
The sample size in this survey was too small to
draw firm conclusions
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Lab Experiment on Web Credibility

• Selected two Web credibility variables for Nina
  Kims thesis experiment
• ads
• typos

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Web credibility researchExperimental Design

• Controlled lab study
• 2X2 mixed design, n 38
• Health information taken from Web
• Independent variables
• typos or no typos
• ads or no ads
• Dependent variables
• questionnaire after viewing

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Web credibility researchSample Stimuli
No typos
Typos
vs
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Web credibility researchSample Stimuli
No Ad
Ad
vs
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Web credibility researchSample Stimuli
Other sample pages
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Web credibility researchWhat did the data show?

• Typos decreased the credibility of page.
• Ads increased the credibility of page.
• Both effects are stronger for vital info than for
  less vital info.

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Level 4 Variables Outside the Web

• Level 1 A First Look at Credibility
• definitions, basic issues
• Level 2 Four Types of Credibility
• different kinds of credibility
• Level 3 Web Site Variables
• web elements and a framework
• Level 4 Variables Outside the Web
• individuals, goals, and contexts
• Level 5 Three Moving Targets
• people, experience levels, and technology

Plus two studies
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Level 4 Variables Outside the Web

• Individual variables
• user differences (age, experience, personality,
  etc.)
• Goal variables
• For example,
• information seeking on health
• surveillance of current events
• passing time, entertainment
• Context variables
• setting
• time factors
• technology factors

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Level 5 Three Moving Targets

• Level 1 A First Look at Credibility
• definitions, basic issues
• Level 2 Four Types of Credibility
• different kinds of credibility
• Level 3 Web Site Variables
• web elements and a framework
• Level 4 Variables Outside the Web
• individuals, goals, and contexts
• Level 5 Three Moving Targets
• people, experience levels, and technology

Plus two studies
43
Level 5 Three Moving Targets

• Three things are changing . . .
• 1. People
• Web user base will become more diversified.
• 2. Experience levels
• Web users will become more savvy.
• 3. Technology
• Web technology and uses will change.
• These moving targets mean . . .
• Perceptions of Web credibility will shift over
  time.
• We need an ongoing effort to understand Web
  credibility.

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Ongoing research efforts at PTL

• Research on web credibility perceptions
• www.webresearch.org
• Web credibility experiments
• Online and in the lab
• Gathering other work on Web credibility
• Pointers at www.webcredibility.org

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In Review

• Level 1 A First Look at Credibility
• definitions, basic issues
• Level 2 Four Types of Credibility
• different kinds of credibility
• Level 3 Web Site Variables
• web elements and a framework
• Level 4 Variables Outside the Web
• individuals, goals, and contexts
• Level 5 Three Moving Targets
• people, experience levels, and technology

Plus two studies
46
What Variables Affect Web Credibility?

• A Report of Ongoing Research from Stanfords
  Persuasive Technology Lab
• BJ Fogg (bjfogg_at_stanford.edu)

First presented at CSLIs Industrial Affiliate
Conference Stanford University, November 11, 1999