Question

A group of veterinarians at a major veterinary hospital was interested in investigating a possible link between enteroliths, stones that form in the colon of horses, and diet. They decided to conduct a survey of feeding practices of horses admitted to the veterinary hospital. To obtain a random sample of the 5000 horses that had been admitted over the last 10 years to the hospital, they sequentially assigned numbers starting with 1 to the horses in order of admittance. They then picked a random starting point and decided to sample every 100th horse to get a random sample of 50 horses. This procedure corresponds to a:

a. simple random sample because all horses have the same chance of being picked.
b. systematic sample because not all sample are possible.c. stratified random sample because the procedure is obviously not a simple random sample.
d. None of the answer choices is correct.

Answer 1

b. systematic sample because not all sample are possible

Explanation:

Since every 100th horse is selected in the sample. Thus, Systematic Sampling is used.

Further,

Sampling method is said to be Simple Random Sampling if unit from the population are drawn randomly without any criteria, such that each unit as same chance of selection.

Sampling method is said to be Systematic Sampling if any criteria is used to chose every sample, say every 4th unit is selected.

Sampling method is said to be stratified sampling if population is divided into different groups of same characteristic. And the units from these groups are randomly select.