Resolving Informational Inefficiencies In Bilateral Trade

Asymmetric information can impede socially efficient trade in bilateral transactions. This dissertation consists of three essays that address how informational inefficiencies can be resolved in three different settings. These approaches to resolve the informational inefficiencies can help explain many characteristics of real estate markets, mergers and acquisitions, OTC markets, etc. The first chapter considers the two-person bargaining problem under asymmetric information as in Myerson and Satterthwaite (1983). The famous Myerson and Satterthwaite\u27s theorem shows that direct bilateral bargaining is generally inefficient. We show that an informed broker, acting as an intermediary between a buyer and seller, can achieve efficient trade. We provide a sufficient condition on the broker\u27s information to achieve an efficient outcome. In the broker\u27s optimal mechanism, while a more informed broker extracts a higher surplus, trade is still more efficient; consequently, the buyer and seller can be better off trading with a more informed broker. In the second chapter, co-authored with Vincent Glode and Christian Opp, we analyze optimal voluntary disclosure by a privately informed buyer who faces a seller endowed with market power in a bilateral transaction. While disclosures reduce the buyer\u27s informational advantage, they may increase his ex ante information rents by mitigating the seller\u27s incentives to resort to inefficient screening. We show that when disclosures are restricted to be ex post verifiable, the buyer always finds it optimal to design a partial disclosure plan that implements socially efficient trade in equilibrium. In the third chapter, co-authored with Vincent Glode and Christian Opp, we consider the limiting result of Glode and Opp (2016). We show that, generically, if efficient trade can be implemented by an incentive-compatible mechanism in direct bilateral trading, it can also be achieved in a sequential trading game with a sufficiently long chain of heterogeneously informed intermediaries

A Sharper Ratio

The Sharpe ratio is the dominant measure for ranking risky assets and funds. This paper derives a generalized ranking measure which, under a regularity condition, is valid in the presence of a much broader assumption (utility, probability) space yet still preserves wealth separation for the broad HARA utility class. Our ranking measure, therefore, can be used with ``fat tails\u27\u27 as well as multi-asset class portfolio optimization. We also explore the foundations of asset ranking, including proving a key impossibility theorem: any ranking measure that is valid at non-Normal ``higher moments\u27\u27 cannot generically be free from investor preferences. Finally, we derive a closed-form approximate measure (that can be used without numerical analysis), which nests some previous attempts to include higher moments. Despite the added convenience, we demonstrate that approximation measures are unreliable even with an infinite number of higher moments

Long-term contracting with time-inconsistent agents

We study contracts between naive present-biased consumers and risk-neutral firms. We show that the welfare loss from present bias vanishes as the contracting horizon grows. This is true both when bargaining power is on the consumers’ and on the firms’ side, when consumers cannot commit to long-term contracts, and when firms do not know the consumers’ naiveté. However, the welfare loss from present bias does not vanish when firms do not know the consumers’ present bias or when they cannot offer exclusive contracts

Long-term contracting with time-inconsistent agents

We study contracts between naive present-biased consumers and risk-neutral firms. We show that the welfare loss from present bias vanishes as the contracting horizon grows. This is true both when bargaining power is on the consumers’ and on the firms’ side, when consumers cannot commit to long-term contracts, and when firms do not know the consumers’ naiveté. However, the welfare loss from present bias does not vanish when firms do not know the consumers’ present bias or when they cannot offer exclusive contracts

Genotype-Corrector: improved genotype calls for genetic mapping in F2 and RIL populations

F2 and recombinant inbred lines (RILs) populations are very commonly used in plant genetic mapping studies. Although genome-wide genetic markers like single nucleotide polymorphisms (SNPs) can be readily identified by a wide array of methods, accurate genotype calling remains challenging, especially for heterozygous loci and missing data due to low sequencing coverage per individual. Therefore, we developed Genotype-Corrector, a program that corrects genotype calls and imputes missing data to improve the accuracy of genetic mapping. Genotype-Corrector can be applied in a wide variety of genetic mapping studies that are based on low coverage whole genome sequencing (WGS) or Genotyping-by-Sequencing (GBS) related techniques. Our results show that Genotype-Corrector achieves high accuracy when applied to both synthetic and real genotype data. Compared with using raw or only imputed genotype calls, the linkage groups built by corrected genotype data show much less noise and significant distortions can be corrected. Additionally, Genotype-Corrector compares favorably to the popular imputation software LinkImpute and Beagle in both F2 and RIL populations

Improving EFL Learners Language Written Production Using Subtitled Videos

English as a Foreign Language (EFL) Learners tend to produce their speech or written production as they are associated with what they see and what they hear. So, they are able and desired to give comment spontaneously after watching and listening to them. Producing written language can, as a matter of fact, be detected from learners\u27 fluency, accuracy and complexity. This article endeavors to elaborate written language production done by university students by using English subtitled videos. Two intact groups were assigned to accomplish two different tasks; that is, one group watched the video with subtitle and the other one without subtitle. The result of the study reveals that learners who carry out the tasks of watching video with subtitle improve their ability in written production in terms of fluency and accuracy regardless to complexity

学会抄録

Mauve visualization of local collinear blocks identified among 14 haplotypes (15BACs) from Saccharum species and sorghum. (DOCX 1909 kb

Comparative structural analysis of Bru1 region homeologs in Saccharum spontaneum and S. officinarum

BACKGROUND: Sugarcane is a major sugar and biofuel crop, but genomic research and molecular breeding have lagged behind other major crops due to the complexity of auto-allopolyploid genomes. Sugarcane cultivars are frequently aneuploid with chromosome number ranging from 100 to 130, consisting of 70–80 % S. officinarum, 10–20 % S. spontaneum, and 10 % recombinants between these two species. Analysis of a genomic region in the progenitor autoploid genomes of sugarcane hybrid cultivars will reveal the nature and divergence of homologous chromosomes. RESULTS: To investigate the origin and evolution of haplotypes in the Bru1 genomic regions in sugarcane cultivars, we identified two BAC clones from S. spontaneum and four from S. officinarum and compared to seven haplotype sequences from sugarcane hybrid R570. The results clarified the origin of seven homologous haplotypes in R570, four haplotypes originated from S. officinarum, two from S. spontaneum and one recombinant.. Retrotransposon insertions and sequences variations among the homologous haplotypes sequence divergence ranged from 18.2 % to 60.5 % with an average of 33.7 %. Gene content and gene structure were relatively well conserved among the homologous haplotypes. Exon splitting occurred in haplotypes of the hybrid genome but not in its progenitor genomes. Tajima’s D analysis revealed that S. spontaneum hapotypes in the Bru1 genomic regions were under strong directional selection. Numerous inversions, deletions, insertions and translocations were found between haplotypes within each genome. CONCLUSIONS: This is the first comparison among haplotypes of a modern sugarcane hybrid and its two progenitors. Tajima’s D results emphasized the crucial role of this fungal disease resistance gene for enhancing the fitness of this species and indicating that the brown rust resistance gene in R570 is from S. spontaneum. Species-specific InDel, sequences similarity and phylogenetic analysis of homologous genes can be used for identifying the origin of S. spontaneum and S. officinarum haplotype in Saccharum hybrids. Comparison of exon splitting among the homologous haplotypes suggested that the genome rearrangements in Saccharum hybrids after hybridization. The combined minimum difference at 19.5 % among homologous chromosomes in S. officinarum would be sufficient for proper genome assembly of this autopolyploid genome. Retrotransposon insertions and sequences variations among the homologous haplotypes sequence divergence may allow sequencing and assembling the autopolyploid Saccharum genomes and the auto-allopolyploid hybrid genomes using whole genome shotgun sequencing. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-016-2817-9) contains supplementary material, which is available to authorized users

The bracteatus pineapple genome and domestication of clonally propagated crops

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a 'one-step operation'. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars 'Smooth Cayenne' and 'Queen' exhibited ancient and recent admixture, while 'Singapore Spanish' supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops