Understanding public relations in the ‘sharing economy’

In spite of the macro-economic impact of the so-called ‘sharing economy’ there is a nearly complete dearth of contributions from the communication academy to its discourse. More attention is overdue, particularly for the conceptual pressure the ‘sharing economy’ is exerting on the public relations function. The authors propose a reconceptualization of public relations by identifying the constitutive aspects of the sharing economy and bringing together the explanatory concepts ‘circuits of commerce’ and ‘viable matches’ from economic sociology and communicative constitution of organizations theory to develop the notions of ‘deliberate disintermediation’ and ‘circuits of communication’ in public relations. The contention is that by doing this, communicative acts not only contribute meaning in the sharing economy, but have economic value. Furthermore, the sharing economy poses challenges to the traditional forms of organizing public relations functions, but offers opportunities to realize different potential when public relations facilitates circuits of communication and becomes a meta-communicative competence embedded within the organization.     

Does Marital History Matter? Marital Status and Wealth Outcomes Among Preretirement Adults

Data from the 1992 Health and Retirement Survey are used to specify ordinary least squares (OLS) regression models predicting wealth. Separate models are estimated for men and women. The results indicate that individuals who are not continuously married have significantly lower wealth than those who remain married throughout the life course. Remarriage offsets the negative effect of a marital dissolution. There are significant gender differences in these effects. The results demonstrate that accounting for the sequence of marital events provides a detailed picture of the life paths that lead to wealth heterogeneity among the older population.     

Long cycles in hypercubes with optimal number of?faulty vertices

Let f(n) be the maximum integer such that for every set F of at most f(n) vertices of the hypercube Q _n , there exists a cycle of length at least 2 ⁿ ?2|F| in Q _n ?F. Casta?eda and Gotchev conjectured that $f(n)=\binom{n}{2}-2$ . We prove this conjecture. We also prove that for every set F of at most (n ²+n?4)/4 vertices of Q _n , there exists a path of length at least 2 ⁿ ?2|F|?2 in Q _n ?F between any two vertices such that each of them has at most 3 neighbors in F. We introduce a new technique of potentials which could be of independent interest.     

Conditional MSE-based discrimination of the sample mean and the post-stratification estimator in population sampling

Whenever a random sample is drawn from a stratified population, the post-stratification estimator $\tilde X$ usually is preferred to the sample mean $\tilde X$ , when the population mean is to be estimated. This is due to the fact that the variance of $\tilde X$ is asymptotically smaller than that of $\tilde X$ , while both estimators are asymptotically unbiased. However, this only holds looking at post-stratification unconditionally, when strata sample sizes are random. Conditioned on the realized sample sizes, the MSE of $\tilde X$ can be higher than that of $\tilde X$ which means that $\tilde X$ should be preferred to $\tilde X$ , even if it is biased. The conditional MSE difference of $\tilde X$ and $\tilde X$ is estimated, and using this estimation and its variance a heuristic test based on the Vysochanskiî-Petunin inequality is derived.     

Transparency in Buyer‐Determined Auctions: Should Quality be Private or Public?

We study buyer‐determined procurement auctions where both price and non‐price characteristics of bidders matter for being awarded a contract. Although, in scoring auctions bidders perfectly know how price and non‐price attributes determine the awarding of the contract, this remains uncertain in buyer‐determined auctions where the buyer is free to choose once all bids have been submitted. We analyze the impact of information bidders have with respect to the buyer's awarding decision. As we show theoretically whether it is in the buyer's interest to conceal the impact of non‐price characteristics depends on how important the quality aspects of the procured good are to the buyer: The more important quality aspects are, the more interesting concealment becomes. In a counterfactual analysis using data from a large European procurement platform, we analyze the reduction of non‐price information available to the bidders. Confirming our hypothesis, for auction categories where bidders’ non‐price characteristics strongly influence buyers’ decisions concealment of non‐price information leads to an increase in buyers’ surplus of up to 15% due to higher competitive pressure and lower bids. Conversely, for categories where bidders’ non‐price characteristics are of little importance concealment of non‐price information leads to a decrease in buyers’ surplus of up to 6%.     

Detecting and explaining systemic risks of mortgage banks—evidence from the subprime crisis

In recent history, financial markets worldwide experienced severe turmoil due to the subprime crisis originating from the practice of US mortgage banks to securitize loans given especially to subprime borrowers. In the same crisis, several distressed banks were bailed out by states with even more banks receiving financial aids from governments. Using a unique data sample of 100 announcements of US mortgage banks between 2006 and 2009, this paper provides empirical evidence that isolated failures of US mortgage banks caused significant contagion effects in the US financial system. Conversely, especially the bailouts of Fannie Mae and Freddie Mac led to significant positive valuation effects at rival banks. In the cross-sectional analyses, contrary to previous studies in the literature on past financial crises, we find evidence for pure contagion effects following the failures of US mortgage banks. Furthermore, we analyze the reactions of the CDS spreads of several large US banks to the announcements of mortgage banks using a novel mixture copula model. The results show that the contagion effects were limited to the stock market thus underlining the notion of an irrational response of (stock) market participants. The results from our cross-sectional and CDS data analyses in turn indicate that several of the failures of US mortgage banks during the subprime crisis caused irrational contagion in the US financial system thus justifying government intervention. Finally, we rule out the possibility that the contagion effects limited to the US stock market were caused by a herding of investors.     

On a neglected aspect of portfolio choice: the role of the invested capital

In return-based portfolio choice models à la Markowitz, the amount of capital invested does not play a role, while in expected utility models it does. The aim of this paper is to bring out the connection between the amount of capital invested and the portfolio formation. In a general one-period framework, which also comprises illiquid assets held by the investor and the period income, we present results in finding the optimal portfolio weights and study the influence of the invested capital, the illiquid assets and the income on the portfolio formation. Special emphasis is put on HARA utility functions and the dependence of the amount invested risklessly on the invested capital. As a side result, we find that Markowitz portfolio choice is not fully compatible with expected utility reasoning.     

纳粹屠杀与南京暴行的研究:范式转变与比较启示

相对于第二次世界大战期间侵华日军南京暴行,纳粹屠杀的研究成果更为丰富、多样和体系化,研究范式经历了从极权主义到结构主义,再到魅力权威的转变.这一转变将加害者从希特勒及纳粹领导层扩展到整个德国社会,进而产生了颠覆性的结果,即第三帝国的犯罪不仅是大规模受害者意义上的大,而且还在于参与者的多;这一转变还揭示纳粹屠杀的受害者不仅仅是犹太人,还包括境内外大量的非犹太人.这一事实表明除了反犹主义外,第三帝国的系列意识形态信条,如民族主义、殖民主义等构造了众多德国人愿意参与纳粹犯罪的条件.民族主义的心态和认同导致了受害者和加害者之间共有的人性感的降低,进而导致后者的道德标准的丧失;殖民活动与种族上的他者的出现使优越感和轻蔑的态度盛行,这些心态提供了纳粹屠杀和南京暴行比较研究的重要起点,而殖民地经历及暴力制度文化则是比较研究的重要内容.