Question

A farmer has a corn field with 150 rows of corn, each containing about 2000 corn plants. He divides the field into 12000 regions of 25 plants each. He then uses the random number generator in Excel to pick 20 regions and checks each of the 25 plants in those regions for disease.

(a) Simple random sampling.
(b) Stratified random sampling.
(c) Cluster random sampling.
(d) Two-stage random sampling.

Answer 1

The farmer's method of using a random number generator to select specific regions in a corn field for disease checking is an example of two-stage random sampling.

Step-by-step explanation:

The farmer's approach to checking for disease in the corn plants involves using a random number generator. This method aligns with the concept of two-stage random sampling. Initially, the field is divided into 12,000 regions, each containing 25 corn plants. This division forms the first stage, where groups are formed, similar to clusters. Then, in the second stage, a random number generator is used to select 20 out of these 12,000 regions, and each plant within the selected regions is examined.

In two-stage sampling, the first stage involves forming groups or clusters (in this case, the regions). The second stage consists of taking a sample within those selected clusters, which the farmer does by examining each of the 25 plants per selected region. Two-stage sampling is particularly useful when it is impractical or costly to conduct a simple random sample of individual items in a large population.