Identifikation von Sparprofilen im Lebenszyklus

A key element of houshold behavior, saving is still not satisfactorily understood. The seminal lif-cycle theory of saving by Modigliani et al has been augmented by the consideration of liquidity constraints, mortality, morbidity, income, interest, and other uncertaities, and, more recently, by behavioral elements. Each of these amendments explains part of saving behavior. However, contradictions remain widespread. This paper poses the question in how far observable age-saving profiles can identify competing theories of saving behavior. The paper departs from the age-saving profiles observed in Germany and compares them with age-saving profiles that were simulated using different variants of augmented life-cycle saving theories. It shows that age-saving profiles per se cannot separate competing theories of saving behavior. This means that the estimations of Euler-equation are not identified.

Rules of Thumb in Life-Cycle Saving Decisions

We analyse life-cycle saving decisions when households use simple heuristics, or rules of thumb, rather than solve the underlying intertemporal optimization problem. We simulate life-cycle saving decisions using three simple rules and compute utility losses relative to the solution of the optimization problem. Our simulations suggest that utility losses induced by following simple decision rules are relatively low. Moreover, the two main saving motives re ected by the canonical life-cycle model { long-run consumption smoothing and short-run insurance against income shocks { can be addressed quite well by saving rules that do not require computationally demanding tasks such as backward induction

Rules of Thumb in Life-Cycle Saving Decisions

We analyse life-cycle saving decisions when households use simple heuristics, or rules of thumb, rather than solve the underlying intertemporal optimization problem. We simulate life-cycle saving decisions using three simple rules and compute utility losses relative to the solution of the optimization problem. Our simulations suggest that utility losses induced by following simple decision rules are relatively low. Moreover, the two main saving motives re ected by the canonical life-cycle model { long-run consumption smoothing and short-run insurance against income shocks { can be addressed quite well by saving rules that do not require computationally demanding tasks such as backward induction.saving; life-cycle models; bounded rationality; rules of thumb

Savings decisions under life-time and earnings uncertainty : empirical evidence from West German household data

We analyze a model of life-cycle savings decisions which allows for both life-time and income uncertainty. We then simulate life-cycle saving rates based on empirical income processes estimated from West German household data. Our main findings are, first, that allowing for mortality risk improves the life-cycle model's predictions slightly, and second, that simulated saving rates still fail to match their empirical counterparts. While our model correctly predicts differential peak saving rates during working life for three household types that face different income processes, it cannot explain an important salient feature of saving in Germany: Empirically, there is almost no post-retirement dissaving, while our life-cycle model predicts substantial dissaving even though we control for the generous German pension system which results in relatively high post-retirement income

Rules of thumb in life-cycle savings models

We analyze life-cycle savings decisions when households use simple heuristics, or rules of thumb, rather than solve the underlying intertemporal optimization problem. The decision rules we explore are a simple Keynesian rule where consumption follows income; a simple consumption rule where only a fraction of positive income shocks is saved; a rule that corresponds to the permanent income hypothesis; and two rules that have been found in experimental studies. Using these rules, we simulate life-cycle savings decisions numerically and compute the utility losses relative to the backwards solution of the intertemporal optimization problem. Our central finding is that the utility losses induced by rule-of-thumb behavior are relatively low. We conclude that behaving optimally, in the sense of solving an intertemporal optimization model, is not only costly, it is also not much better than using simple heuristics. Our results might also explain why optimization models typically fit the main features of empirical data quite well although optimizing behavior itself is frequently rejected

Savings decisions under life-time and earnings uncertainty:

We analyze a model of life-cycle savings decisions which allows for both life-time and income uncertainty. We then simulate life-cycle saving rates based on empirical income processes estimated from West German household data. Our main findings are, first, that allowing for mortality risk improves the life-cycle model's predictions slightly, and second, that simulated saving rates still fail to match their empirical counterparts. While our model correctly predicts differential peak saving rates during working life for three household types that face different income processes, it cannot explain an important salient feature of saving in Germany: Empirically, there is almost no post-retirement dissaving, while our life-cycle model predicts substantial dissaving even though we control for the generous German pension system which results in relatively high post-retirement income.

Rules of Thumb in Life-Cycle Savings Models

We analyze life-cycle savings decisions when households use simple heuristics, or rules of thumb, rather than solve the underlying intertemporal optimization problem. The decision rules we explore are a simple Keynesian rule where consumption follows income; a simple consumption rule where only a fraction of positive income shocks is saved; a rule that corresponds to the permanent income hypothesis; and two rules that have been found in experimental studies. Using these rules, we simulate life-cycle savings decisions numerically and compute the utility losses relative to the backwards solution of the intertemporal optimization problem. Our central finding is that the utility losses induced by rule-of-thumb behavior are relatively low. We conclude that behaving optimally, in the sense of solving an intertemporal optimization model, is not only costly, it is also not much better than using simpler heuristics which do not require backward induction. Our results might also explain why optimization models typically fit the main features of empirical data quite well although optimizing behavior itself is frequently rejected.

"Household Savings in Germany"

This paper describes how German households save and how their saving behavior is linked to public policy, notably pension policy. The analysis is based on a synthetic panel of four cross sections of the German Income and Expenditure Survey ("Einkommens- und Verbrauchsstichproben," EVS,1978, 1983, 1988, and 1993). The paper carefully distinguishes between several saving measures and concepts. It separates discretionary savings from mandatory savings and uses two flow measures: first, the sum of purchases of assets minus the sum of sales of assets and, second, the residual of income minus consumption. Our main finding is a hump-shaped age-saving profile with a high overall saving rate. However, savings remain positive in old age, even for most low-income households. How can we explain what may be termed the "German savings puzzle"? Germany has one of the most generous public pension and health insurance systems in the world, yet private savings are high until old age. We provide a complicated answer that combines historical facts with capital market imperfections and a distinction between the role of discretionary and mandatory savings.

The German Savings Puzzle

Germany has one of the most generous public pension and health insurance systems of the world, yet private savings are high until old age. Savings remain positive in old age, even for most low income households. How can we explain what we might want to term the 'German savings puzzle?' We provide a complicated answer that combines historical facts with capital market imperfections, housing, tax and pension policies. The first part of the paper describes how German households save, based on a synthetic panel of four cross sections of the German Income and Expenditure Survey ('Einkommens- und Verbrauchsstichproben') collected between 1978 and 1993. The second part links saving behavior with public policy, notably tax and pension policy.

Household Savings in Germany

This paper describes how German households save and how their saving behavior is linked to public policy, notably pension policy. The analysis is based on a synthetic panel of four cross sections of the German Income and Expenditure Survey ("Einkommens- und Verbrauchsstichproben," EVS, 1978, 1983, 1988, and 1993). The paper carefully distinguishes between several saving measures and concepts. It separates discretionary savings from mandatory savings and uses two flow measures: first, the sum of purchases of assets minus the sum of sales of assets and, second, the residual of income minus consumption. Our main finding is a hump-shaped age-saving profile with a high overall saving rate. However, savings remain positive in old age, even for most low-income households. How can we explain what may be termed the "German savings puzzle"? Germany has one of the most generous public pension and health insurance systems in the world, yet private savings are high until old age. We provide a complicated answer that combines historical facts with capital market imperfections and a distinction between the role of discretionary and mandatory savings.