Final answer:
The correct answer to whether association equals causation is 'B. Sometimes'. While two variables may be associated, this does not necessarily imply that one causes the other. Correlation does not equal causation, and the existence of potential confounding variables must be considered.
Step-by-step explanation:
Association and causation are concepts often discussed in scientific research, especially in observational studies. To answer the question 'Does association equal causation?' the correct response would be 'B. Sometimes'. While there can be a causal relationship between two associated variables, it is not a guaranteed outcome that one causes the other. A key example to illustrate this is mentioned in Chapter 2 involving ice cream sales and burglaries. Both increase together but are likely influenced by a third variable such as the weather. This exemplifies that correlation does not inherently imply causation, and further investigation is required to establish a definitive cause-and-effect relationship.
To avoid the confusion between correlation and causation, researchers must look for potential confounding variables that might explain the correlation. One historic case involved the research linking smoking and cancer. While the correlation was strong, researchers needed to carefully rule out other explanations before confidently asserting causation. Therefore, understanding the distinction between correlation and causation is crucial in critically analyzing the results from any observational study.