
Concept explainers
In Problems 1 and 2, determine if the sampling is dependent or independent indicate whether the response variable is qualitative or quantitative.
1. A researcher wants to know if the mean length of stay in for-profit hospitals is different from that in not-for-profit hospitals. He randomly selected 20 individuals in the for-profit hospital and matched them with 20 individuals in the not-for-profit hospital by diagnosis.

To indicate: Whether the response variable is qualitative or quantitative variable.
Answer to Problem 1RE
The sampling isdependent.
The response variable is quantitative variable.
Explanation of Solution
Given info:
There are 2 groups in which 20 subjects are randomly allocated for group 1 and 20 subjects are randomly allocated for group 1. Also, the subjects are matched by diagnosis.
Justification:
Independent sample:
If the individuals from one sample do not associate with the individuals from other sample, then the two samples are said to be independent samples.
Dependent sample:
If the individuals from one sample is associated with the individuals from other sample, then the two samples are said to be dependent samples.
Here, the subjects are taken from the two groups and the subjects are matched by diagnosis. This indicates that the data are matched according to some inherent relationships. Therefore, the sampling isdependent.
Qualitative Variable:
It is used to classify the individuals on some attribute or characteristic.
Quantitative Variable:
It gives a numerical measurement of the individuals of population. The values of quantitative variables can be added or subtracted to get meaningful result.
Also, the response variable is the length of stay. Hence, the response variable gives a numerical measurement of the individuals of a sample.
Thus, the response variable is quantitative variable.
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