Measurement Scales

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Measurement Scales

• Continuous vs. Discrete Variables
• Types of Scales
• Nominal, Ordinal, Interval, and Ratio

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Scales of measurement

• Nominal - label and categorize without making
  quantitative distinctions (political party,
  football player jersey numbers)
• Ordinal - rank observations in terms of size or
  magnitude (Scale of Life Stress, US News and
  World Reports college rankings, Mohs hardness
  scale)
• Nominal and Ordinal Scales are Discrete
• A discrete variable consists of separate,
  indivisible categories. No values can exist
  between two neighboring categories.

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Scales of measurement

• Interval - equal differences between numbers
  reflect equal differences in magnitude
  (temperature scales, IQ scores)
• Ratio - interval scale with additional feature of
  an absolute zero point (e.g., time, length,
  volume)
• Interval and Ratio Scales are Continuous
• For a continuous variable, there are an infinite
  number of possible values that fall between any
  two observed values. A continuous variable is
  divisible into fractional parts.

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Questionnaire Results
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Questionnaire Results
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Questionnaire Results
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Questionnaire Results
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Exploratory Data Analysis
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Creating a Frequency Distribution
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Creating a Frequency Distribution
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Frequency Distribution Table (ungrouped)
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Frequency Distribution Table (grouped)
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Ungrouped Frequency Histogram
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Grouped Frequency Distribution
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Gee-Wiz Graphs
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Gee Whiz Graphs
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Gee-Wiz Graphs