The question of whether two drugs - namely alcohol and tobacco - are used as complements or substitutes is of crucial interest if side-effects of anti-smoking policies are considered. Numerous papers have empirically addressed this issue by estimating demand systems for alcohol and tobacco and...

We test whether financial incentives have an effect on weight reduction in a randomized controlled trial involving 700 obese persons assigned to three experimental groups. While two treatment groups obtain €150 and €300, respectively, for achieving an individually assigned target weight...

This paper investigates gender differences in smoking behavior using data from the German Socio-economic Panel (SOEP). We develop a Blinder-Oaxaca decomposition method for count data models which allows to isolate the part of the gender differential in the number of cigarettes daily smoked that...

This paper examines the effect of copayments on doctor visits using the German health care reform of 2004 as a natural experiment. In January 2004, copayments of 10 euros for the first doctor visit in each quarter have been introduced for all adults in the statutory health insurance. Individuals...

This paper investigates the method of matching regarding two crucial implementation choices, the distance measure and the type of algorithm. We implement optimal full matching - a fully efficient algorithm - and present a framework for statistical inference. The implementation uses data from the...

This paper outlines why program evaluation should follow well-respected scientific standards and why it should be performed by independent researchers.

Recently, building on the highly polarizing Stiglitz report, a growing literature suggests that statistical offices and applied researchers explore other aspects of human welfare apart from material well-being, such as job security, crime, health, environmental factors and subjective...

Compulsory military service typically drafts young men when they are at the height of their learning ability. Thus, it can be expected to depress the demand for higher education since skill atrophy and the delayed entry into the civilian labor market reduce the returns to human-capital...

Volunteering plays a prominent role in the charitable provision of goods and services, yet we know relatively little about why individuals spend time and money to the charity. Assuming that volunteering is a consumption good, we analyze the determinants of individuals' charitable cash donations...

We identify the causal effect of compulsory military service on conscripts' subsequent labor-market outcomes by exploiting the regression-discontinuity design of the military draft in Germany during the 1950s. Unbiased estimates of the effect of military service on lifetime earnings, wages, and...