(Original source: http://www.emersonstatistics.com/datasets/fev.doc)
It is now widely believed that smoking tends to impair lung function. Much of the data to support this claim arises from studies of pulmonary function in adults who are long-time smokers. A question then arises whether such deleterious effects of smoking can be detected in children who smoke. To address this question, measures of lung function were made in 654 children seen for a routine check up in a particular pediatric clinic. The children participating in this study were asked whether they were current smokers.
A common measurement of lung function is the forced expiratory volume (FEV), which measures how much air you can blow out of your lungs in a short period of time. A higher FEV is usually associated with better respiratory function. It is well known that prolonged smoking diminishes FEV in adults, and those adults with diminished FEV also tend to have decreased pulmonary function as measured by other clinical variables, such as blood oxygen and carbon dioxide levels.
This data contains information on 654 children. Each row corresponds to a single clinic visit. Missing data is denoted by NA. The following variables are available:
seqnbr: case number (the numbers 1 to 654)subjid: subject identification number (unique for each different child)age: subject age at time of measurement (years)fev: measured FEV (liters per second)height: subject height at time of measurement (inches)sex: subject sex (male, female)smoke: smoking habits (smoker, nonsmoker)