The data refer to a study on low birthweight in babies, defined as "less than 2500 grams", and related factors.
The variables are:
||indicator of whether the mother is a smoker|
||last menstrual weight of the mother|
||indicator variable of low weight|
Hosmer & Lemeshow (1989). Applied Logistic Regresion. Wiley, NY. The original source contains additional variables; see Appendix 1 of Hosmer & Lemeshow for a full list of the data, pp.29-30 and p.92 for additional information.