A test of the Bolton-Scheinkman-Xiong hypothesis of how speculation affects the vesting time of options granted to directors

This paper investigates empirically the Bolton, Scheinkman, and Xiong (2006) hypothesis, according to which initial shareholders may provide incentives to managers to take actions that stimulate speculative bubbles. We test this hypothesis with data on up to 8,544 directors and up to 1,677 companies between 2004-2008. Using vesting time as a measure of the short-term performance weighting in CEO compensation and various alternative measures of the extent of speculation, the findings support the hypothesis: vesting time decreases with more intensive speculation. The results prove robust in various empirical model specifications.

Uniqueness of the Embedding Continuous Convolution Semigroup of a Gaussian Probability Measure on the Affine Group and an Application in Mathematical Finance

Let {μ(i)t}t≥0 ( i=1,2 ) be continuous convolution semigroups (c.c.s.) of probability measures on Aff(1) (the affine group on the real line). Suppose that μ(1)1=μ(2)1 . Assume furthermore that {μ(1)t}t≥0 is a Gaussian c.c.s. (in the sense that its generating distribution is a sum of a primitive distribution and a second-order differential operator). Then μ(1)t=μ(2)t for all t≥0 . We end up with a possible application in mathematical finance.

Efficacy of topical tacrolimus for oral lichen planus: real-life experience in a retrospective cohort of patients with a review of the literature

BACKGROUND AND OBJECTIVE Management of oral lichen planus (OLP) is challenging and therapeutic options are limited. The use of topical tacrolimus has shown promising results. We reviewed our daily life experience with topical tacrolimus in OLP patients. METHODS This retrospective unicentre study included all 21 patients with OLP, which were evaluated over a 53-month period and treated with topical tacrolimus. Patients were initially given a topical preparation of 0.1% tacrolimus twice daily. The response to treatment was assessed using a 4-point scale at month 2 and 6: complete response of affected area (CR), major remission (>50%, MR), partial remission (25-50%, PR) and either no response (<25%) or worsening. The pain score was also assessed using a 3-point scale. RESULTS Four of 21 patients (19%) showed a CR at month 2, whereas at month 6, 7 (33%) had a CR. For patients who reported MR (n = 2) and PR (n = 8) at month 2, the therapy was continued. Of those, at 6 months, three patients showed a CR, while four maintained a PR. The pain score improved during treatment. After 2 months of therapy, eight of 10 patients with an initial high pain score achieved a significant improvement. In patients starting with moderate pain an improvement was observed in one of seven patients. Overall, for three patients there was a complete loss of pain, while in nine there was a reduction. Except for transitory burning sensation and altered taste sensation, no relevant side-effects were reported. CONCLUSION This retrospective analysis confirms that topical tacrolimus is a valuable therapeutic option in severe or treatment-resistant OLP. Our findings in daily practice suggested nevertheless that the efficacy of topical tacrolimus is overestimated with regard to both complete response and pain reduction.