"An important class of investment decisions is characterized by unrecoverable sunk costs, resolution of uncertainty through time, and the ability to invest in the future as an alternative to investing today. The options model provides guidance in such settings, including an investment decision...

The time household members in industrialized countries spend on housework and shopping is substantial, amounting on average to about half as much time as is spent on paid employment. Women bear the brunt of this burden, a difference that is driven in part by the gender differential in wages....