STRENGTHS & STRENGTHS & LIMITATIONS OF ALL LIMITATIONS OF ALL

EIGHT EVIDENCE TYPESEIGHT EVIDENCE TYPES

Data from Personal Experience/Anecdotal Datao Personal experience examples help readers identify with writer; they show writer’s personal connection to the issue.o Skeptics may sometimes argue that personal experience examples are insufficient (writer is guilty of hasty generalization), not typical, or not adequately scientific or verifiable. 

Data from Observation or Field Research

o It increases typicality by expanding database beyond example of one person

oSkeptics may point to flaws in how observations were conducted, showing how data are insufficient, inaccurate, or nontypical.

Data from Interviews, Questionnaires, Surveys

o These forms of evidence enhance the sufficiency and typicality of evidence by expanding the database beyond the experience of one person.o Skeptics can raise doubts about research methodology, questionnaire design (inherently biased questions), or typicality of interview subjects. 

Data from Library or Internet Research/Vital Facts

o Researched evidence is often powerful, especially when sources are respected by your audience; writers can spotlight source’s credentials through attributive tags.

o Skeptics might doubt the accuracy of facts, the credentials of a source, or the research design of a study. They might also cite studies with different results.

o Skeptics might raise doubts about sufficiency, typicality, or relevance of your research data.

Expert Testimony/Authority Opinion

o Persuasiveness can be increased if source has impressive credentials which the writer can state through attributive tags introducing the testimony.

o Skeptics might undermine testimony evidence by questioning credentials of source, showing source’s bias, or quoting a countersource.

Statistical Data

o Statistics can give powerful snapshots of aggregate data from a wide database.

o Skeptics might question statistical methods, research design, and interpretation of data

Hypothetical Examples, Cases, and Scenarios

o They are persuasive only if they seem plausible.o Skeptics might show the implausibility of the scenario or offer an alternative scenario.

 

Reasoned Sequence of IdeasoThese sequences are often used in causal

arguments to show how causes are linked to effects or in definitional or values arguments to show links among ideas.

oTheir effectiveness depends on the audience’s acceptance of each link in the sequence of ideas.

o Skeptics might raise objections at any link in the sequence, often by pointing to different values or outlining different consequences.