Final answer:
A survey with a randomly selected subset of respondents receiving different topical modules is called a split ballot. Different sampling methods, such as simple random, stratified, systematic, and cluster, are used based on the study's needs. The split ballot method can help understand question wording effects.
Step-by-step explanation:
A survey in which a randomly selected subset of respondents where 50% receive a survey on one topical module while the other 50% receives a survey on a different module is called a split ballot. This technique is often used to gauge how different questions or wordings affect responses, which can be important in understanding question wording effects.
In contrast, a survey design like the one where a market researcher polls every tenth person is called systematic sampling. Meanwhile, when a survey aims to represent a larger population accurately and gives every person an equal chance of being chosen, it employs a random sample. Such a method is crucial for ensuring the success of scientific polls, including national Gallup Polls.
Sampling methods like simple random, stratified, systematic, and cluster each have specific procedures and are used based on the particular needs of a study. To measure public opinion effectively, researchers must choose the appropriate sampling method while remaining aware of potential biases, such as those introduced by leading questions or a non-representative sample.