This document discusses data preparation and description. It covers editing data to ensure accuracy, consistency, completeness and uniformity. Coding establishes category sets for data that are appropriate, exhaustive, mutually exclusive and derived from one principle. Descriptive statistics describe data distribution through measures of location, spread, and shape such as mean, median, mode, variance, standard deviation, range, interquartile range, skewness and kurtosis.

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2. Part Four
ANALYSIS AND
PRESENTATION OF DATA
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McGraw-Hill/Irwin © 2003 The McGraw-Hill Companies, Inc.,All Rights Reserved.

3. Chapter Fifteen
DATA PREPARATION AND
DESCRIPTION
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4. Editing
• Detects errors and omissions,
• Corrects them when possible, and
• Certifies that minimum data quality
standards are achieved
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5. Editing (cont.)
• Guarantees that data are
– accurate
– consistent with other information
– uniformly entered
– complete
– arranged to simplify coding and
tabulation
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6. Editing
• Field Editing
– translation of ad hoc abbreviations
and symbols used during data
collection
– validation of the field results.
• Central Editing
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7. Coding
• Rules that guide the establishment of
category sets
– Appropriate to the research problem
and purpose
– Exhaustive
– Mutually exclusive
– Derived from one classification
principle
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8. Content Analysis for Coding
• Measures the semantic content of a
message
• Researches the objective, systematic,
and quantitative description of the
content of a communication
– Syntactical unit
– Referential unit
– Propositional unit
– Thematic unit
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9. Data Entry Options
• Optical scanning
• Voice recognition
• Keyboard
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10. Data Entry Formats
• Database with full screen editor
• Spreadsheet
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11. Descriptive Statistics
• Distribution Descriptors
– Location
– Spread
– Shape
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12. Descriptive Statistics
• Distribution Descriptors
– Location
• Central Tendency
– Mean
– Median
– Mode
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13. Descriptive Statistics
• Distribution Descriptors
– Spread
• Variance,
• Standard Deviation,
• Range,
• Interquartile Range
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14. Descriptive Statistics
• Distribution Descriptors
– Shape
• Skewness
• Kurtosis
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