Final answer:
The sampling method used is Systematic sampling, where every nth element is chosen from the population. This method ensures a representative sample and equal chances for all members.
Step-by-step explanation:
The sampling method used in this study is Systematic sampling. In systematic sampling, the researcher selects every nth element from the population. In this case, the researcher shuffled the deck of playing cards and chose the top 20 cards, which represents a systematic selection process.
An example of systematic sampling is when a teacher wants to select students for a group project and decides to choose every 5th student from the class roster. By selecting every nth element, the sample is representative of the population and ensures that all members have an equal chance of being included.
The type of sampling described in the question - writing everyone's name on a playing card, shuffling the deck, then choosing the top 20 cards - is simple random sampling. This method gives each individual an equal chance to be included in the sample because every possible sample of the given size has the same chance of being chosen. In simple random sampling, neither ordering nor stratification is utilized; selection is purely by chance, ensuring that the sample data is not biased towards any group within the population.