Mining History of Gamification Towards Finding Expertise in Question and Answering Communities: Experience and Practice with Stack Exchange

Recently, an online Q&A tool has become an essential part of individual communities and organizations of experts on specific topics. Using the answers to questions about specific topics will help such communities work more efficiently in their fields. Currently, Q&A online communities are adopting gamification to engage users by granting awards to successful users. In this paper, we investigate how to mine award achievement histories to find expertise. We propose the use of sequence analysis and clustering techniques. Specifically, we study the history of Stack Exchange, a large Q&A community that employs gamification. To the best of our knowledge, this is the first study of using award achievement history to find expertise in Q&A communities.     

Sarbanes-Oxley Act and corporate credit spreads

Stock market reaction suggests that despite improved disclosure and increased accountability, Sarbanes-Oxley Act (SOX) is too costly and not beneficial. Noting that bondholders are likely to reap the many potential benefits of SOX without bearing the brunt of costs, we examine how SOX affected corporate credit spreads to better assess its benefits. SOX has led to a significant structural decline in spreads of at least 27 basis points. Riskier firms (low rating, long maturity, high leverage, and small size) and firms closely related to SOX major provisions (earning variability, managerial trading, and corporate governance) experience greater declines in spreads.     

Does citizen participation affect municipal performance? Electoral competition and fiscal performance in Japan

Subnational fiscal performance has been receiving a lot of attention from researchers in various disciplines. However, there is very little published on the impact of citizen involvement on fiscal performance. This paper shows that a lack of citizen involvement in the electoral process was associated with fiscal performance in all 807 city-level Japanese municipalities from 2006 to 2012.     

Amino acid formula as a new strategy for diagnosing cow’s milk allergy in infants: is it cost-effective?

Aims: To estimate the cost-effectiveness of a new strategy that uses an amino acid formula in the elimination diet of infants with suspected cow’s milk allergy (CMA).

Materials and methods: This pharmacoeconomic study was developed from the perspective of the Brazilian Public Healthcare System. The new strategy proposes using an amino acid formula in the diagnostic elimination diet of infants (≤24 months) with suspected CMA. The rationale is that infants who do not respond to the amino acid formula do not suffer from CMA. Patients with a positive oral challenge test receive a therapeutic elimination diet based on Brazilian Food Allergy Guidelines. This approach was compared to the current recommendations of the Brazilian Food Allergy Guidelines. A decision model was constructed using TreeAge Pro 2012 software. Model inputs were based on a literature review and the opinions of a panel of experts. A univariate sensitivity analysis of incremental cost-effectiveness ratios was performed.

Results: The mean cost per patient of the new amino acid formula strategy was R$3,341.57, while the cost of the current Brazilian guidelines strategy was R$3,641.08. The mean number of symptom-free days per patient, which was used as an indicator of effectiveness, was 900.6 and 875.7 days, respectively. The new strategy is, therefore, dominant. In the sensitivity analysis, the dominance was maintained with parameter variation.

Limitations: In the absence of information in the literature, some premises were defined by a panel of specialists.

Conclusions: The new strategy, which uses an amino acid formula in the elimination diagnostic diet followed by an oral food challenge, is a dominant pharmacoeconomic approach that has a lower cost and results in an increased number of symptom-free days.     

BOND MARKET REACTION TO STOCK REPURCHASES: IS THERE A WEALTH TRANSFER EFFECT?

We reexamine the bondholder wealth impact of stock repurchases with a focus on the wealth transfer effect. We do not detect any transfer of wealth from bondholders to shareholders surrounding open market stock repurchases. For the overall sample (1994–2002), using daily data we document a significant decrease in bond yields surrounding repurchase announcements. Subsamples classified by attributes that capture wealth transfer propensity also do not reveal evidence consistent with a wealth transfer effect. Correlation analysis between bond and stockholder wealth effects similarly is not supportive of a wealth transfer effect. Contrary to the wealth transfer hypothesis, we document a greater proportion of bond rating upgrades than downgrades in the three months following a repurchase announcement. Our results are robust to alternate bond price data and event return methodology.     

Are mutual fund fees excessive?

There is a long running debate over whether competition in the mutual fund industry limits the ability of investment advisors to charge fees that are disproportionate to the services they provide. We posit that disproportionately high fees are prevalent in funds with multiple share classes and those with weak governance structures. Using a comprehensive sample of index mutual funds for the from 1998 to 2007, we find that internal governance mechanisms matter primarily for funds with relatively small share classes where investors often face increased search costs and/or restricted access to competitive mutual funds. Additionally, we find that funds managed by publicly held sponsors are associated with disproportionately higher fee spreads (about 28 basis points). The results are robust to the inclusion of board characteristics, share class structure, and investment objectives. Overall, our findings suggest that competition and agency considerations are important determinants in the pricing of mutual funds.     

Empowering leadership and meaningful work: the mediating role of learning goal orientation

Drawing on positive psychology and self‐determination theories, this study investigates the direct and indirect effects of empowering leadership on meaningful work of employees, particularly through the mediation of learning goal orientation. Longitudinal survey data of 388 employees in medical institutions were used to test the hypotheses. The results support the direct positive relationship between empowering leadership and meaningful work, but also emphasize the mediating effect of learning goal orientation within this relationship. This study is among the first to examine the effect of mediation by learning goal orientation upon the relationship between empowering leadership and meaningful work.     

Alternation of parties in power and economic volatility: testing the rational partisan hypothesis and policy learning hypothesis

Right and left parties have distinct macroeconomic preferences that could create different levels of volatility during their executive tenures. But rational partisan theory argues that, because actors in the economy anticipate ruling party behavior, partisan differences only matter when election outcomes are uncertain. We argue that policy risk from ruling parties extends beyond elections, leading to important variation in growth volatility that occurs during a ruling party’s tenure. Building on theories of policy risk and learning, we argue that after elections, economic actors still face uncertainty about the policies of new ruling parties. With time in power, new ruling parties build policy track records, reducing policy risk and, thus, volatility. We estimate a learning curve model of ruling party duration’s effect on the variation in quarterly GDP growth rates. Using data from 44 democracies between 1981 and 2009, we find that learning processes extend beyond the conclusion of uncertain elections.