Researchers can judge the relations

Researchers can judge the relationship between variables that are difficult to observe, such as how often people engage in safer sex.
Another advantage of surveys is the ability to sample representative segments of the population.
As long as the sample is selected randomly, we can assume that the responses are a reasonable match to those of the population as a whole.

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Peneliti bisa menilai hubungan antara variabel-variabel yang sulit untuk mengamati, seperti bagaimana orang sering terlibat dalam seks yang aman.Keuntungan lain dari survei adalah kemampuan untuk sampel perwakilan segmen dari populasi. Sebagai contoh dipilih secara acak, kita dapat mengasumsikan bahwa tanggapan pertandingan yang wajar bagi penduduk secara keseluruhan.