Question

In: Statistics and Probability

A physician decdes to take a random sample of hospitals in a large metropolitan area. From...

A physician decdes to take a random sample of hospitals in a large metropolitan area. From each hospital included in the sample he takes a random sample of house-staff physcians. He interviews the physicians to determine where they attended medical school. The sample design used in this study is an example of: (1 mark)

Systematic random sample
Stratified random sample
Simple cluster sample
Two stage cluster sample
Haphazard sample

Investigations in which the student units are stimulated in some way and the researcher observes a response is called ( 1 mark)

Observational studies
Prospective studies
Sample studies
Experimental studies
Retrospective studies

Expert Solution

Ans:

d) Two stage cluster sample

here physician decides to take a random sample of hospitals in a large metropolitan area. Hence this is cluster sampling . After selecting randomly cluster, takes a random sample of house-staff physcians from selected hospitals. This is extension of cluster sampling . So this design is Two stage cluster sampling .

Remaining options are incorrect because:

Here no systematic pattern is observed.

Subgroups are not according to common attributes.

Samples are randomly selected from clusters.

Ans:

d)Experimental studies

Here the units are simulated and are totally under control. Due to under the direct control of the investigator this is an Experimental study.

in an observational study, the investigator only observe and does not intervene.

In Prospective studies units are observed even before experiment is carried out.

The sample study is simply the studying the sample units from the population.

Retrospective studies uses record and not experiment.

orchestra answered 2 years ago

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