Quantitative analysis involves the use of statistical tools to process numerical data. The most common method is calculating the arithmetic mean, which provides a central value for a dataset by summing all observations and dividing by the total count ().
When calculating the mean, precision is vital. Results should typically be rounded to one decimal place; if the second decimal digit is 5 or higher, the first digit is rounded up, whereas if it is 4 or lower, it remains the same.
Anomalies are data points that deviate significantly from the established pattern or trend. These must be identified during analysis and can be caused by human error (misreading equipment), faulty instruments, or localized environmental variations (e.g., measuring wind speed in a sheltered 'wind shadow').
Qualitative analysis focuses on non-numerical evidence, such as annotated photographs and field sketches. These tools allow researchers to record the visual context of a site, such as the presence of wind-breaks or the specific layout of a microclimate.
Annotations are critical in qualitative work; they should not just label features but explain their significance to the enquiry. For example, an annotation might link a tall building in a photograph to the 'canyon effect' that increases localized wind speeds.
| Feature | Reliability | Validity |
|---|---|---|
| Definition | The consistency of the results if the study were repeated. | The extent to which the study actually measures what it intended to measure. |
| Focus | Precision, equipment accuracy, and sample size. | Enquiry design, appropriate variables, and correct site selection. |
| Improvement | Use digital equipment or take more readings over time. | Ensure sample sites are not biased and secondary data is relevant. |
Understanding the difference between Primary and Secondary data is essential for planning. Primary data offers high relevance but can be limited by time and equipment, while secondary data offers scale and historical depth but may not be perfectly aligned with the specific study area.
Graph Completion: You are often required to finish a partially drawn graph. Always use a ruler for bar graphs and ensure the width of your new bars matches the existing ones exactly.
Showing Workings: In calculation questions (like finding the mean), always write out the full addition and division steps. Marks are frequently awarded for the process even if the final answer has a minor rounding error.
Identifying Anomalies: Look for points on a scattergraph that sit far away from the line of best fit. When asked to explain them, consider both human error and environmental factors.
Evaluation Questions: For 8-mark questions, you must make a judgment. Don't just describe what you did; explain why it was successful or how specific limitations (like faulty equipment) reduced the reliability of your conclusions.
