Presentation on theme: "Evaluating Evidence. Bell Ringer Evaluating Evidence Reliable evidence should come from a source that is reputable, authoritative (or expert) and without."— Presentation transcript:
Evaluating Evidence Reliable evidence should come from a source that is reputable, authoritative (or expert) and without a motive to mislead. Statistics and other numerical evidence can mislead even if there is no motive involved. We need to question what is being hidden by the evidence, what is not being said, what is being twisted or manipulated and what has been omitted because it did not fit in with the aim of the writer.
When evaluating evidence consider the following questions: Is this evidence meaningful? Who funded the survey or research? What was the size of any sample? Was the sample representative? How was any survey conducted? When was the survey carried out? Are examples typical and relevant? Are research findings clear-cut or ambiguous?
Percentages and Proportions Percentages can be a valuable tool for presenting data. However, percentages are often presented in ways that are misleading or provide no useful information. Is the percentage given here useful?
The ‘average’ or mean The term ‘average’ is often used carelessly. How is the term ‘average’ misleading in this example?
Numerical and statistical evidence presented as graphs, diagrams, or images Very often it is easier to understand information if it is presented in visual form than if it is simply explained in text.