Module 10: Data Collection Methods

Quantitative Approach

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• Data in numerical form
• Data that can be precisely measured
• age, cost, length, height, area, volume, weight, speed, time, and temperature
• Harder to develop
• Easier to analyze

Qualitative Approach

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• Data that deal with description
• Data that can be observed or self-reported, but not always precisely measured
• Less structured, easier to develop
• Can provide “rich data” — detailed and widely applicable
• Is challenging to analyze
• Is labor intensive to collect
• Usually generates longer reports

Which Data?

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• - do not need to quantify the results

• - are not sure what you are able to measure

• Qualitative

• - want narrative or in-depth information

• - want to cover a large group

• want to be precise
• know what you want to measure

• Quantitative

• - want to conduct statistical analysis

• Then Use:

• If you:

Obtrusive vs. Unobtrusive Methods

• Obtrusive
• data collection methods that directly obtain information from those being evaluated
• e.g. interviews, surveys, focus groups

• Unobtrusive data collection methods that do not collect information directly from evaluees
• e.g., document analysis, GoogleEarth, observation at a distance, trash of the stars

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How to Decide on Data Collection Approach

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• Choice depends on the situation
• Each technique is more appropriate in some situations than others
• Caution: All techniques are subject to bias