Inducing R&D investment with price ceilings

Though government intervention is prevalent in the market for research and development (R&D), most literature has focused on the use of subsidies, patents or joint research ventures to obtain the efficient R&D investment. By using a two-stage duopoly model in which firms first choose the level of investment and then output, our paper shows that the introduction of a price ceiling by the regulator will result in the optimal level of R&D. This interesting but counterintuitive result contrasts with the existing literature and advances our understanding about price ceilings.Research and development; Subsidy; Price ceiling

Single field inflation with modulated potential in light of the Planck and BICEP2

The recently released BICEP2 data detected the primordial B-mode polarization in the Cosmic Microwave Background (CMB) map which strongly supports for a large tensor-to-scalar ratio, and thus, is found to be in tension with the Planck experiment with no evidence of primordial gravitational waves. Such an observational tension, if confirmed by forthcoming measurements, would bring a theoretical challenge for the very early universe models. To address this issue, we in the present paper revisit a single field inflation model, which includes a modulated potential. We show that this inflation model can give rise to a sizable negative running behavior for the spectral index of primordial curvature perturbation and a large tensor-to-scalar ratio. Applying these properties, our model can nicely explain the combined Planck and BICEP2 observations. To examine the validity of analytic calculations, we numerically confront the predicted temperature and B-mode power spectra with the latest CMB observations and explicitly show that our model is consistent with the current data.Comment: 8 pages, 6 figure

Safety and immunogenicity of an MF59™-adjuvanted subunit influenza vaccine in elderly Chinese subjects

BACKGROUND: The safety and immunogenicity of an MF59™-adjuvanted subunit influenza vaccine (Sub/MF59™; FLUAD(®), Novartis Vaccines) was evaluated among elderly Chinese subjects (≥ 60 years of age). After a preliminary Phase I, open-label study (n = 25) to assess safety 1–14 days post-vaccination, a comparative observer-blind, randomised, controlled clinical trial (n = 600) was performed to assess safety and immunogenicity versus a non-adjuvanted subunit influenza vaccine (Subunit; Agrippal(®), Novartis Vaccines). Subjects were randomised (2:1) to receive Sub/MF59™ or Subunit. RESULTS: Both vaccines were well tolerated, with no vaccine-related serious adverse events reported during the Phase I trial. During the observer-blind study, local and systemic reactions were generally similar for both vaccines 1–22 days post-vaccination; however, injection-site induration was more frequent among the Subunit group (P < 0.05), and mild pain at the injection site and fever were more frequent among Sub/MF59™ recipients (P ≤ 0.005). Both vaccines induced a significant (P < 0.001) increase in geometric mean titres (GMTs) for the three strains tested, versus baseline; GMTs against A/H1N1, A/H3N2 and B were significantly higher in the Sub/MF59™ group (P = 0.034, P < 0.001 and P = 0.005, respectively). GMT ratios against A/H1N1, A/H3N2 and B were also significantly higher in the Sub/MF59™ group (P = 0.038, P < 0.001 and P = 0.006, respectively). Similarly, the percentage of subjects achieving seroprotection or seroconversion on Day 22 was greater for Sub/MF59™ recipients, reaching significance for A/H3N2 (P < 0.001). CONCLUSION: MF59™-adjuvanted subunit influenza vaccine is well tolerated by elderly Chinese subjects and induces a higher level of immunogenicity than a non-adjuvanted subunit influenza vaccine in this population that is at high risk of influenza-related complications. CLINICAL TRIAL REGISTRY: , NCT0031064

Essays on Timing of Firm Actions in Industrial Economics

The timing of actions by firms plays an important role in industrial economics. It is key to strategic advantage in oligopoly models whether firms compete on quantity or on price. In a vertical relationship between input suppliers and final-good manufacturers, a firm which chooses a strategy first will take into account the response by those firms moving second and different sequence of play leads to different market outcomes. In my dissertation, I study the determinants and implications of the timing of firm actions in a variety of scenarios. In my first two essays, I examine how market leadership may arise endogenously in oligopoly models and focus on the effect of information about uncertain market demand. My first essay studies a quantity game and I identify the circumstance under which a perishable information asymmetry regarding stochastic demand causes market leadership. In an information acquisition game, I show that Stackelberg equilibrium in the full game is supported only when firms have different costs of information. My second essay considers a duopoly in which firms supply a differentiated product and compete on price. I find that different equilibrium outcomes arise under different information structures. Under asymmetric information, a firm’s information advantage leads to a strategic disadvantage of leading in the price game. The time value of information may well be negative, contrasting with results in the first essay. In my third essay, I consider a vertical relationship in which a supplier sets the price of an input and the firm that produces the final good must choose how much to invest in some complementary input or process. Two models with different sequence of firm actions are studied and yield different pricing strategies for the upstream monopolist. Interestingly, a change of the sequence from one model (the upstream firm commits to input prices first) to the other (the upstream firm sets input prices after investments are made) benefits all parties including the upstream monopolist, the downstream firms and the consumers

A Hybrid Machine Learning-Based Method for Classifying the Cushing's Syndrome With Comorbid Adrenocortical Lesions

Background: The prognosis for many cancers could be improved dramatically if they could be detected while still at the microscopic disease stage. It follows from a comprehensive statistical analysis that a number of antigens such as hTERT, PCNA and Ki-67 can be considered as cancer markers, while another set of antigens such as P27KIP1 and FHIT are possible markers for normal tissue. Because more than one marker must be considered to obtain a classification of cancer or no cancer, and if cancer, to classify it as malignant, borderline, or benign, we must develop an intelligent decision system that can fullfill such an unmet medical need. Results: We have developed an intelligent decision system using machine learning techniques and markers to characterize tissue as cancerous, non-cancerous or borderline. The system incorporates learning techniques such as variants of support vector machines, neural networks, decision trees, self-organizing feature maps (SOFM) and recursive maximum contrast trees (RMCT). These variants and algorithms we have developed, tend to detect microscopic pathological changes based on features derived from gene expression levels and metabolic profiles. We have also used immunohistochemistry techniques to measure the gene expression profiles from a number of antigens such as cyclin E, P27KIP1, FHIT, Ki-67, PCNA, Bax, Bcl-2, P53, Fas, FasL and hTERT in several particular types of neuroendocrine tumors such as pheochromocytomas, paragangliomas, and the adrenocortical carcinomas (ACC), adenomas (ACA), and hyperplasia (ACH) involved with Cushing's syndrome. We provided statistical evidence that higher expression levels of hTERT, PCNA and Ki-67 etc. are associated with a higher risk that the tumors are malignant or borderline as opposed to benign. We also investigated whether higher expression levels of P27KIP1 and FHIT, etc., are associated with a decreased risk of adrenomedullary tumors. While no significant difference was found between cell-arrest antigens such as P27KIP1 for malignant, borderline, and benign tumors, there was a significant difference between expression levels of such antigens in normal adrenal medulla samples and in adrenomedullary tumors. Conclusions: Our frame work focused on not only different classification schemes and feature selection algorithms, but also ensemble methods such as boosting and bagging in an effort to improve upon the accuracy of the individual classifiers. It is evident that when all sorts of machine learning and statistically learning techniques are combined appropriately into one integrated intelligent medical decision system, the prediction power can be enhanced significantly. This research has many potential applications; it might provide an alternative diagnostic tool and a better understanding of the mechanisms involved in malignant transformation as well as information that is useful for treatment planning and cancer prevention

Costimulatory molecule-deficient dendritic cell progenitors (MHC class II⁺, CD80(dim), CD86^-) prolong cardiac allograft survival in nonimmunosuppressed recipients

We have shown previously that granulocyte-macrophage colony-stimulating factor-stimulated mouse bone marrow-derived MHC class II+ dendritic cell (DC) progenitors that are deficient in cell surface expression of the costimulatory molecules B7-1 (CD8O) and B7-2 (CD86) can induce alloantigen- specific T-cell anergy in vitro. To test the in vivo relevance of these findings, 2 x 106 B10 (H2(b)) mouse bone marrow-derived DC progenitors (NLDC 145+, MHC class II+, B7-1(dim), B7-2(-/dim)) that induced T-cell hyporesponsiveness in vitro were injected systemically into normal C3H (H2(k)) recipients. Seven days later, the mice received heterotopic heart transplants from B10 donors. No immunosuppressive treatment was given. Median graft survival time was prolonged significantly from 9.5 to 22 days. Median graft survival time was also increased, although to a lesser extent (16.5 days), in mice that received third-party (BALB/c; H2(d)) DC progenitors. Ex vivo analysis of host T-cell responses to donor and third-party alloantigens 7 days after the injection of DC progenitors (the time of heart transplant) revealed minimal anti-donor mixed leukocyte reaction and cytotoxic T lymphocyte reactivity. These responses were reduced substantially compared with those of spleen cells from animals pretreated with 'mature' granulocyte- macrophage colony-stimulating factor + interleukin-4-stimulated DC (MHC class II(bright), B7-1+, B7-2(bright)), many of which rejected their heart grafts in an accelerated fashion. Among the injected donor MHC class II+ DC progenitors that migrated to recipient secondary lymphoid tissue were cells that appeared to have up-regulated cell surface B7-1 and B7-2 molecule expression. This observation may explain, at least in part, the temporary or unstable nature of the hyporesponsiveness induced by the DC progenitors in nonimmunosuppressed recipients

Timing of investments and third degree price discrimination in intermediate good markets

We study third degree price discrimination in intermediate good markets, in which costs of production for the downstream firms are determined by their investment choices. We focus on the effect of the sequence of firm actions and analyze two models with different timing of investments, before or after the upstream monopolist sets the input prices. When investments are determined after the prices are set, an indirect effect of input prices on the derived demand from downstream firms must be taken into account, due to the change of investment incentives. This causes the upstream firm to possibly charge the more efficient downstream firm a lower price, a result contrasting previous findings. Using linear demand and quadratic investment costs, we show that not only the downstream firms but also the upstream monopolist prefers the sequence of play in the latter model, i.e., it benefits from committing to prices before investments are undertaken. A change of timing from the first model to the second constitutes a strict Pareto improvement

Timing of investments and third degree price discrimination in intermediate good markets

We study third degree price discrimination in intermediate good markets, in which costs of production for the downstream firms are determined by their investment choices. We focus on the effect of the sequence of firm actions and analyze two models with different timing of investments, before or after the upstream monopolist sets the input prices. When investments are determined after the prices are set, an indirect effect of input prices on the derived demand from downstream firms must be taken into account, due to the change of investment incentives. This causes the upstream firm to possibly charge the more efficient downstream firm a lower price, a result contrasting previous findings. Using linear demand and quadratic investment costs, we show that not only the downstream firms but also the upstream monopolist prefers the sequence of play in the latter model, i.e., it benefits from committing to prices before investments are undertaken. A change of timing from the first model to the second constitutes a strict Pareto improvement