The article Heartfelt Thanks to Fido san Luis Obispo Tribune

The article “Heartfelt Thanks to Fido” (san Luis Obispo Tribune, July 5, 2003) summarized a study that appeared in the American Journal of Cardiology (March 15, 2003). In this study researchers measured heart rate variability (a measure of heat’s ability to handle stress) in patients who had recovered from a heart attack. They found that heart rate variability was higher (which is good and means the heart can handle stress better) for those who owned a dog than for those who did not.

a. There are two variables (one response variable and one explanatory variable) in this particular research study. What are those two variables? Identify the variables as either qualitative or quantitative. Identify the variables as either discrete, continuous, or neither.

Solution

Owning a dog is a explanatory variable and and heart rate variability is a response variable

Owning a dog is a qualitative characteristic or variable as a person can posses it or not

Variability in the heart rate is a quantitative variable as it can be measured

Owning a dog is a descrete or indicator variable taking value as 1 if person owns a dog or 0 if person does not owns a dog

Variability in heart beat is continuous variable