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ERIC Number: EJ908040
Record Type: Journal
Publication Date: 2010-Dec
Pages: 6
Abstractor: ERIC
Reference Count: 10
ISSN: ISSN-0145-482X
Looking for Power: The Difficulties and Possibilities of Finding Participants for Braille Research
Wright, Tessa
Journal of Visual Impairment & Blindness, v104 n12 p775-780 Dec 2010
Power analysis, in its most basic form, is a calculation of the different design characteristics of a study to determine if certain aspects of the study are robust enough to detect a significant difference between groups if a significant difference exists. These characteristics include effect size, the difference between the means of the groups being compared relative to the variability within those groups; alpha, the level of risk that statistically significant differences are found when they do not actually exist; and the number of participants in the study, which affects how accurately the sample represents the population as a whole. Power can be calculated using a formula, but is easily determined by reviewing power tables that are found in statistical reference books or software online. By considering and calculating power and including design features that increase power when planning a study, the chance of failing to find significant differences between the groups when significant differences exist, simply because the research design is not stringent enough, is diminished. As an illustration of the possibility of conducting an experimental study with students who read braille, the author makes reasonable assumptions about how a study would be designed and, keeping power in mind, examines the possibility of finding enough participants for a study in the hypothetical situation presented in this article. (Contains 2 tables and 1 figure.)
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Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A