For those interested in the research results using the Groceries dataset and how the support, confidence, and lift measurements are defined, you can refer to the following papers:

• Michael Hahsler, Kurt Hornik, and Thomas Reutterer (2006) Implications of Probabilistic Data Modeling for Mining Association Rules. In M. Spiliopoulou, R. Kruse, C. Borgelt, A
• Nuernberger, and W. Gaul, editors, From Data and Information Analysis to Knowledge Engineering, Studies in Classification, Data Analysis, and Knowledge Organization, pages 598-605. Springer-Verlag

Also, in addition to using the summary and inspect functions to inspect association rules, you can use interestMeasure to obtain additional interest measures:

> head(interestMeasure(rules, c("support", "chiSquare", "confidence", 
"conviction","cosine", "coverage", "leverage", "lift","oddsRatio"),
 Groceries))