家戶組成與家庭儲蓄的共同決策

The Joint Determination of Household Formation and Saving

江莉莉(Lily Jiang)

《經濟論文叢刊》 31卷1期 (2003/03) Pp. 1-25

https://doi.org/10.6277/ter.2003.311.1

摘要

本研究建構一個家庭組成與儲蓄的共同決策模型。在一個三期、跨代的生命不確定模型下，假設自利的二代採用Nash協商架構，本文導出二代共組家戶的條件，與各自的消費函數及家庭儲蓄函數。就儲蓄行為而言，與自立門戶的核心家庭不同的是，二代所組成的折衷家庭之儲蓄分別受到子女的所得與父母的積蓄之影響，同時也考量父母的生命風險與對家庭型態的偏好。利用比較靜態分析與數值模擬，本文發現無論哪一類型的折衷家庭，其儲蓄率均較自立門戶下低。惟如以儲蓄量論，折衷家庭未必少於核心家庭；孰多孰少端視二代各自的資源與偏好而定。又當外在環境改變時，家庭成員間的相互威脅互有消長，因而重啟協商之門，調整家戶的組成方式與資源配置。不同類型的折衷家庭，其反應未盡相同。這些結論提醒我們，欲完全掌握與瞭解社會儲蓄的變動，必須審視家庭成員間的互動效果與家庭型態改變的影響。

關鍵字

家戶組成 ； 家庭儲蓄 ； 生命不確定性 ； Nash協商

並列摘要

The paper develops a joint model of intergenerational living and saving decisions. Facing an uncertain lifetime, selfish parent and children agree to a Nash bargaining rule to determine jointly the household membership and consumption path of each member. With risk-sharing arrangements, savings at the household level depend not only on each member's resources, but also on both generations' survival probabilities and preferences for co residence. Comparative statics and simulation analyses all show that the saving ratios in the joint living states are amounts of saving between the two types of living arrangements are indeterminate. The paper also investigates the impact of changes in tastes, resources and survival probabilities for each member on the decisions of household restructuring and saving. The implication is that to examine the changes in social savings, we should take interactions between the two generations and household restructuring into account.

並列關鍵字

household formation ； saving ； uncertain lifetime ； Nash bargaining

參考文獻

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