University of Mannheim

About: University of Mannheim is a education organization based out in Mannheim, Germany. It is known for research contribution in the topics: Context (language use) & Politics. The organization has 4448 authors who have published 12918 publications receiving 446557 citations. The organization is also known as: Uni Mannheim & UMA.

An Economic History of Fertility in the U.S.: 1826-1960 ⁄

Abstract: In this paper we use data from the US census to document the history of the relationship between fertility choice and key economic indicators at the individual level for women born between 1826 and 1960. We find that this data suggests several new facts that should be useful for researchers trying to model fertility. (1) The reduction in fertility known as the Demographic Transition (or the Fertility Transition) seems to be much sharper based on cohort fertility measures compared to usual measures like Total Fertility Rate; (2) The baby boom was not quite as large as is suggested by some previous work; (3) We find a strong negative relationship between income and fertility for all cohorts and estimate an overall income elasticity of about -0.38 for the period; (4) We also find systematic deviations from a time invariant isoelastic relationship between income and fertility. The most interesting of these is an increase in the income elasticity of demand for children for the 1876-1880 to 1906-1910birth cohorts. This implies an increased spread in fertility by income which was followed by a dramatic compression. (authors)

Probing Pretrained Language Models for Lexical Semantics

Abstract: The success of large pretrained language models (LMs) such as BERT and RoBERTa has sparked interest in probing their representations, in order to unveil what types of knowledge they implicitly capture. While prior research focused on morphosyntactic, semantic, and world knowledge, it remains unclear to which extent LMs also derive lexical type-level knowledge from words in context. In this work, we present a systematic empirical analysis across six typologically diverse languages and five different lexical tasks, addressing the following questions: 1) How do different lexical knowledge extraction strategies (monolingual versus multilingual source LM, out-of-context versus in-context encoding, inclusion of special tokens, and layer-wise averaging) impact performance? How consistent are the observed effects across tasks and languages? 2) Is lexical knowledge stored in few parameters, or is it scattered throughout the network? 3) How do these representations fare against traditional static word vectors in lexical tasks 4) Does the lexical information emerging from independently trained monolingual LMs display latent similarities? Our main results indicate patterns and best practices that hold universally, but also point to prominent variations across languages and tasks. Moreover, we validate the claim that lower Transformer layers carry more type-level lexical knowledge, but also show that this knowledge is distributed across multiple layers.

Manufacturing network configuration in supply chains with product recovery

Abstract: Efficient implementation of product recovery requires appropriate network structures. In this paper, we study the network design problem of a firm that manufactures new products and remanufactures returned products in its facilities. We examine the capacity decisions and expected performance of two alternative manufacturing network configurations when demand and return flows are both uncertain. Concerning the market structure, we further distinguish between the case where newly manufactured and remanufactured products are sold on the same market and the case where recovered products have to be sold on a secondary market. We consider network structures where manufacturing and remanufacturing are both conducted in common plants as well as structures that pool all remanufacturing activities in a separate plant. The underlying decision problems are formulated as two-stage stochastic programs with recourse. Based on numerical studies with normally distributed demands and returns, we show that particularly network size, investment costs of (re-)manufacturing capacity, and market structure have a strong impact on the choice of a network configuration. Concerning the general role of manufacturing configuration in a system with product recovery, our results indicate that the investigated structures can lead to very different expected profits. We also examine the sensitivity of network performance to changes in return volumes, return variability and correlation between return and demand. Based on these results, we find that integrated plants are more beneficial in the common market setting. This relative advantage tends to diminish when demand is segmented, thus investing in more specialized, dedicated resources should be considered.

How Riskily Do I Invest? The Role of Risk Attitudes, Risk Perceptions, and Overconfidence

Abstract: Our study analyzes the determinants of investors' risk-taking behavior. We find that investors' risk-taking behavior is affected by their subjective risk attitude in the financial domain and by the risk and return of an investment alternative. Our results also suggest that, consistent with previous findings in the literature, the objective, or historical, return and volatility of a stock are worse predictors of risk-taking behavior than subjective risk and return measures. Moreover, we illustrate that overconfidence, or more precisely, miscalibration, has an impact on risk behavior as predicted by theoretical models. However, our results regarding the effect of various determinants on risk-taking behavior heavily depend on the content domain in which the respective determinant is elicited. We interpret this as an indication for an extended content domain specificity. In particular, with regard to the Markets of Financial Instruments Directive, we believe practitioners could improve on their investment advising process by incorporating some of the determinants that, by our argument, influence investment behavior.