In the 1992-93 period, nearly 40 percent of households in the United States purchased breakfast away from home and about 75 percent purchased lunch or dinner during a two-week span. Using a double-hurdle model in this study, the authors report that the wife's employment has a positive effect on the probability and level of lunch and dinner expenditures. Income also has a statistically significant and positive effect.
This working paper was published as Jensen, Helen H. and Steven T. Yen, "Food Expenditures Away From Home by Type of Meal," Canadian Journal of Agricultural Economics 44 (1996): 67–80, doi:10.1111/j.1744-7976.1996.tb00143.x.
Available at: http://works.bepress.com/helen-jensen/100/