A student counts species with a pitfall trap and calculates a diversity index. Why should she use random sampling?
Answer and explanation
Correct answer: B. To avoid bias in the sample
- Step 1: Random sampling gives every area an equal chance of being selected.
- Step 2: This avoids bias and gives a representative sample.
Answer
To avoid bias in the sample.
Why not the others: To make sure that only common species are counted: this would be biased. To save the cost of buying equipment: random placement has nothing to do with cost. To make the experiment faster: speed is not the aim.
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