1. Ch.11 Being Credible
and using evidence
Maria Subert

2. What is source credibility and why is it
important?
• Source credibility is the audience’s perception of the speaker’s effectiveness.
• Audiences do not want to hear from someone they do not trust or respect.
• Source credibility is NOT something a speaker possesses. The audience
determines credibility.

3. Credibility
• Aristotle noted that the speaker’s character is the most effective means of
persuasion.
• Finding ways to trust your audience that you are trustworthy and qualified is
among the most important objectives for the speaker.
• You have to be a credible source when you speak.

4. What are the dimensions of credibility?
• Competence: the degree to which the speaker is perceived as killed, qualified,
experienced, authoritative, reliable and informed. Be familiar with your topic. Don’t
relay on extensive notes, translate ideas and make them understandable to your
audience. Deliver your speech well.
• Trustworthiness: the degree to which the speaker is perceived as honest, fair,
sincere, honorable, friendly, and kind. Use reliable sources, present other viewpoints
as well. Talk confidently, maintain eye-contact.
• Dynamism: the degree to which the speaker is perceived asbold, active, energetic,
strong, emphatic, and assertive. Exhibited by voice, movement, facial expressions,
and gestures.

5. What are the dimensions of credibility?
• Common ground: the degree to which the speaker’s values, beliefs attitudes
and interests are shared with the audience.
Point to shared objective, experiences, or shared circumstances when
you speak.

6. Looking for information
• Personal experiences
• People resources: find the right people and databases
• Written & visual resources: ask reference librarian for help.
• Internet

7. How do you search the Internet for resources?
Internet resources:
• use search engine
• refine your search
• evaluate sources

8. How to cite information correctly?
• Bibliographic reference: Complete citations in “references” or “works
cited” section
• Internal references: brief notations indicating a bibliographic reference
containing the detail(s) you are using in your speech.
• Verbal citation: oral explanation who the source is, how recent the
information is, and what the source’s qualifications are

9. Support your argument
• You use supporting material to
• Substitute your argument
• Clarify your position

10. Support your argument
• Use narratives
• Use surveys
• Testimonial evidences (what others experienced)
• Numbers and statistics
• Analogies
• Explanation
• Definitions

11. How should you use supporting material
ethically?
• Obligation to find the best source of information
• Avoid plagiarism: cite your source of information
• Avoid unfair, inaccurate representation of sources