Quantitative Economics
Journal Of The Econometric Society
Edited by: Stéphane Bonhomme • Print ISSN: 1759-7323 • Online ISSN: 1759-7331
Quantitative Economics: Mar, 2012, Volume 3, Issue 1
Families as roommates: Changes in U.S. household size from 1850 to 2000
Alejandrina Salcedo, Todd Schoellman, Michèle Tertilt
Living arrangements have changed enormously over the last two centuries. While
the average American today lives in a household of only three people, in 1850
household size was twice that figure. Furthermore, both the number of children
and the number of adults in a household have fallen dramatically. We develop
a simple theory of household size where living with others is beneficial solely
because the costs of household public goods can be shared. In other words, we
abstract from intrafamily relations and focus on households as collections of
roommates. The model’s mechanism is that rising income leads to a falling expen-
diture share on household public goods, which endogenously makes household
formation less beneficial and privacy more attractive. To assess the magnitude of
this mechanism, we first calibrate the model to match the relationship between
household size, consumption patterns, and income in the cross section at the end
of the 20th century. We then project the model back to 1850 by changing income.
We find that our proposed mechanism can account for 37 percent of the decline
in the number of adults in a household between 1850 and 2000, and for 16 percent
of the decline in the number of children.
Keywords. Household size, living arrangements, roommates, economies of scale,
household public goods, fertility decline.
the average American today lives in a household of only three people, in 1850
household size was twice that figure. Furthermore, both the number of children
and the number of adults in a household have fallen dramatically. We develop
a simple theory of household size where living with others is beneficial solely
because the costs of household public goods can be shared. In other words, we
abstract from intrafamily relations and focus on households as collections of
roommates. The model’s mechanism is that rising income leads to a falling expen-
diture share on household public goods, which endogenously makes household
formation less beneficial and privacy more attractive. To assess the magnitude of
this mechanism, we first calibrate the model to match the relationship between
household size, consumption patterns, and income in the cross section at the end
of the 20th century. We then project the model back to 1850 by changing income.
We find that our proposed mechanism can account for 37 percent of the decline
in the number of adults in a household between 1850 and 2000, and for 16 percent
of the decline in the number of children.
Keywords. Household size, living arrangements, roommates, economies of scale,
household public goods, fertility decline.
Supplemental Material
Journal News
March 5, 2024
Announcing the New Journal Editors
The terms of the Editors of the Econometric Society's three journals end June 30, 2025. We are pleased to announce the incoming Editors and to thank the outgoing Editors for their excellent and continuing service.
Econometrica: Since 2019, Guido Imbens has served as the 14th Editor of Econometrica. On July 1, 2025, Marina Halac will become the Editor.
Quantitative Economics: Stéphane Bonhomme has been the Editor of Quantitative Economics since 2021. His successor will be Bernard Salanié.
Theoretical Economics: The Editor of Theoretical Economics since 2021 has been Simon Board. Taking over for him in July 2025 will be Federico Echenique.
Guido, Stéphane, and Simon have been outstanding Editors. We are grateful to them for the work they have done and will continue to do, and we look forward to further congratulating them next year. We believe Marina, Bernard, and Federico will be outstanding successors and we thank them in advance for their service.
Finally, we are grateful to Larry Samuelson for chairing all three search committees, and we thank the search committee members for their hard and fruitful work:
Econometrica: Christian Dustmann, Lars Hansen, Alessandro Lizzeri, George Mailath, Ariel Pakes, Helene Rey, and Elie Tamer.
QE: Kate Ho, Michael Keane, Felix Kubler, Whitney Newey, and Frank Schorfheide.
TE: Jeff Ely, Johannes Horner, Gilat Levy, Meg Meyer, and Ran Spiegler.
