Final answer:
Qualitative measurement is used for data that are unstructured and from less formal sources. For example, data on park usage frequency is quantitative discrete, while the duration of visits would be quantitative continuous. House color is qualitative data, while using every eighth house in a survey is an example of systematic sampling.
Step-by-step explanation:
The type of measurement where data are from less formal sources and usually unstructured in nature is known as qualitative measurement. Qualitative data are often collected through observations, interviews, and open-ended questions, resulting in non-numeric data that is categorized based on properties, attributes, labels, or descriptive terms. In contrast, quantitative measurement involves structured data collection and provides numerical data that can be analyzed statistically. Quantitative data can be further divided into discrete or continuous categories depending on whether the data points are countable and distinct, or can take on any value within a range.
For example, when considering the number of times per week that residents use a local park, this would be quantitative discrete data because the number of times is countable. The duration (amount of time) they spend at the park, on the other hand, would typically be quantitative continuous data, as time can be measured to various degrees of precision. In terms of the sampling method used in the survey, if residents of every eighth house were interviewed, this would constitute a systematic sampling technique. Lastly, the colors of the houses around the park would be considered qualitative (categorical) data, as colors are descriptive and cannot be quantified.