* Qualitative measurements describe qualities or characteristics. They deal with descriptions, categories, and meanings. The data gathered is non-numerical. Think of it as answering "what kind?"
* Quantitative measurements describe quantities or amounts. They deal with numbers and measurements. The data gathered is numerical and can be measured and analyzed statistically. Think of it as answering "how much?" or "how many?".
Here's a table summarizing the differences:
| Feature | Qualitative Measurement | Quantitative Measurement |
|-----------------|-------------------------------------------------------|------------------------------------------------------|
| Data Type | Descriptive, categorical, textual | Numerical, measurable |
| Measurement | Observation, interviews, focus groups, surveys (open-ended) | Instruments, scales, surveys (multiple choice, rating scales) |
| Analysis | Interpretation, thematic analysis, content analysis | Statistical analysis (mean, median, standard deviation, etc.) |
| Examples | Color, texture, taste, smell, opinions, attitudes | Height, weight, temperature, age, speed, test scores |
In short: If you can count it or measure it with a number, it's quantitative. If you can only describe it with words, it's qualitative. However, there can be some overlap and gray areas; some measurements might involve both types of data.