Theory of decisions by intra-dimensional comparisons

Making a choice between multidimensional alternatives is a difficult task. Therefore, a decision maker may adopt some procedure (heuristic) to simplify this task. We provide an axiomatic model of one such heuristic called the Intra-Dimensional Comparison (IDC) heuristic. The IDC heuristic is well-documented in the experimental literature on choice under risk. The IDC heuristic is a procedure in which a decision maker compares multidimensional alternatives dimension-by-dimension and makes a decision based on those comparisons. The model of the IDC heuristic provides a general framework applicable to many different contexts, including risky choice and social choice

Democratic transition and the electoral process in Mongolia

This thesis is a study democratic transition paradigm in Mongolia from its communist past to its present status as a democratic country. The study is informed by the democratic transition paradigm by Guillermo O’Donnell and Philippe Schmitter and by the work of Thomas Carothers, a critic of that paradigm. It examines the effectiveness of this theoretical work in guiding the study of an emergent democracy and in that context focuses on the role of elections as well as other internal factors, as well as historical and external factors relevant to democratic transitions. The study finds that both transition paradigm and Carothers’s work are useful guides to understanding the Mongolian case but also it finds flaws in each of them

Choosing with the Worst in Mind: A Reference-Dependent Model

We develop an axiomatic model of reference-dependent preferences in which reference points are menu-dependent. In particular, we focus on choices from menus of two-attribute alternatives, and the reference point for the given menu is a vector that consists of the minimums of each dimension of the menu. We characterize this model by two weakenings of the Weak Axiom of Revealed Preference (WARP) in addition to standard axioms. Our model is consistent with the attraction effect and the compromise effect, well-known deviations from rational choice theory, and it provides a connection between the two effects and diminishing sensitivity, a widely used behavioral property in economics. We apply the model to two different contexts, intertemporal choice and risky choice, and diminishing sensitivity has interesting implications. In intertemporal choice, the main implication of the model is that borrowing constraints produce a psychological pressure to move away from the constraints even if they are not binding. This implication provides a rationale for two empirical puzzles of life-cycle consumption profiles. In risky choice, the model allows different degrees of risk-aversion

Alkaloids from Sedum telephium L.

The crude alkaloid mixtures from the aerial parts S.telephium was analyzed by GC-MS method. As a result 14 compounds, including 6 alkaloids were characterized. 3-methyl-2-carbethoxyindole (4.730%), 2-(2-hydroxyphenyl) benzothiazole (1.576%) and N,4, 5-trimethyl phenyl-1,2-diamine, (1.217%) were in higher contents. One sulfur-containing alkaloid 2-(2-hydroxyphenyl) benzothiazole has been identified. These six alkaloids are described for the first time from this plant.Mongolian Journal of Chemistry 16 (42), 2015, 44-4

Two new alkaloids from the aerial parts of Caryopteris mongolica Bunge

DOI: http://dx.doi.org/10.5564/mjc.v13i0.159 Mongolian Journal of Chemistry Vol.13 2012: 41-4

GC-MS analysis and antibacterial activity of some fractions from Lagochilus ilicifolius Bge. grown in Mongolia

3-methyl-1,2,3,4-tetrahydroquinoline (1), 4-hydroxyisoquinoline (2), 4-(1E)-hydroxy-1-prophenyl)-2-methoxyphenol (3), 4-acetoxycinnamic acid (4), Songoramine (5), and Songorine (6) have been determined by GC-MS analysis from the crude alkaloid mixtures (G1) obtained from the aerial parts of Lagochilus ilicifolius Bge. grown in Mongolia and comparison of the measured data with those from the literature. The compounds 1-6 are described for the first time from L.ilicifolius. From these 3-methyl-1,2,3,4-tetrahydroquinoline (1) was determined for the first time from natural plants.In addition, the antibacterial activity of fractions and total alkaloids were evaluated against Staphylococcus aurous, Bacillus subtilis, Bacillus cereus and Escherichia coli strains, respectively. The growth inhibition zones against gram-positive S.aureus, B.subtilis, B.cereus and gram negative E.coli, strains were observed. Positive results were achieved on 500 μg/disc concentration, but lower results or no active on 100 μg/disc concentration were for the plant extracts, fractions and total alkaloids.Mongolian Journal of Chemistry 16 (42), 2015, 39-4

Synthesis and Biological Evaluation of New Imidazolium and Piperazinium Salts of Pyropheophorbide-a for Photodynamic Cancer Therapy

We have designed imidazolium and piperazinium salts of pyropheophorbide-a in order to develop effective photosensitizers which have good solubility in polar and non polar media and to reveal the possible influences of the piperazine and imidazole moieties on the biological activities of pyropheophorbide-a. The phototoxicity of those pyropheophorbide-a salts against A549 cells was studied in vitro and compared with that of pyropheophorbide-a. The result showed that complexing piperazine and imidazole into pyropheophorbide-a decreases its dark toxicity without greatly decreasing phototoxicity and, enhances its phototoxicity without greatly increasing dark toxicity, respectively. This work not only describes novel amphiphilic salt complexes of pyropheophobide-a which retain the biological activities of the parent compound pyropheophorbide-a and could be effective candidate for PDT, but also reveals the possibility of developing effective photosensitizers by complexing imidazole and piperazine into other hydrophobic photosensitizers

Effects of feed intake restriction during late pregnancy on the function, anti-oxidation capability and acute phase protein synthesis of ovine liver

Objective An experiment was conducted to investigate the effects of feed intake restriction during late pregnancy on the function, anti-oxidation capability and acute phase protein synthesis of ovine liver. Methods Eighteen time-mated ewes with singleton fetuses were allocated to three groups: restricted group 1 (RG1, 0.18 MJ ME/kg W0.75 d, n = 6), restricted group 2 (RG2, 0.33 MJ ME/kg W0.75 d), n = 6) and a control group (CG, ad libitum, 0.67 MJ ME/kg W0.75 d, n = 6). The feed restriction period was from 90 days to 140 days of pregnancy. Results The ewe’s body weight, liver weights, water, and protein content of liver in the restricted groups were reduced compared with the CG group (p0.05). Conclusion The fat accumulation, increased hepatic fibrosis, antioxidant imbalance and modified synthesis of acute phase proteins were induced in ewe’s liver by maternal malnutrition during late pregnancy, which were detrimental for liver function to accommodate pregnancy

Essays in Behavioral Decision Theory

Many different behavioral phenomena that cannot be rationalized by standard models in economics have been well-documented both in the real world and in lab experiments. Motivated by these behavioral phenomena, the purpose of this dissertation is three-fold. First, I develop axiomatic models of individual decision-making to explain these well-documented phenomena. Second, I derive the implications and predictions of these axiomatic models for intertemporal choice, asset pricing, and other economic contexts. Third, I provide connections between these seemingly separate behavioral phenomena and widely-used properties of preferences in economics and psychology. This dissertation consists of five chapters. The first chapter studies dynamic choice under uncertainty. The second and third chapters study choice over multi-attribute alternatives. The fourth and fifth chapters study stochastic choice. The first chapter studies history-dependent risk aversion and focuses on a behavioral phenomenon called the reinforcement effect (RE), which states that people become less risk-averse after a good history than after a bad history. The RE is well-documented in consumer choices, financial markets, and lab experiments. I show that this seemingly anomalous behavior occurs whenever risk preferences are history-dependent (in a nontrivial way) and satisfy monotonicity with respect to first-order stochastic dominance. To study history-dependent risk aversion and the RE formally, I develop a behaviorally-founded model of dynamic choice under risk that generalizes standard discounted expected utility. To illustrate the usefulness of my model, I apply it to the Lucas tree model of asset pricing and draw implications of the RE for asset price dynamics. I find that, compared to history-independent models, assets are overpriced when the economy is in a good state and are underpriced in a bad state. Moreover, my model generates high, volatile, and predictable asset returns, and low and smooth bond returns, consistent with empirical evidence. In the second chapter, I develop an axiomatic model of reference-dependent preferences in which reference points are endogenous. In particular, I focus on choices from menus of two-attribute alternatives, and the reference point for a given menu is a vector that consists of the minimums of each dimension of the menu. I characterize this model by two weakenings of the Weak Axiom of Revealed Preference (WARP) in addition to standard axioms. My model is not just consistent with the attraction effect and the compromise effect, well-known preference reversals, but it also provides a connection between these two effects and diminishing sensitivity, a widely used behavioral property in economics. The model also provides bounds on preference reversals. I apply the model to two different contexts, intertemporal choice and risky choice, and diminishing sensitivity has interesting implications. In intertemporal choice, the main implication of the model is that borrowing constraints produce a psychological pressure to move away from the constraints even if they are not binding. In risky choice, the model allows conflicting risk behaviors. In the third chapter, I study choice over multidimensional alternatives. Making a choice between multidimensional alternatives is a difficult task. Therefore, a decision maker may adopt some procedure (heuristic) to simplify this task. I provide an axiomatic model of one such heuristic called the Intra-Dimensional Comparison (IDC) heuristic. The IDC heuristic is well-documented in the experimental literature on choice under risk. The IDC heuristic is a procedure in which a decision maker compares multidimensional alternatives dimension-by-dimension and makes a decision based on those comparisons. The model of the IDC heuristic provides a general framework applicable to many different contexts, including risky choice and social choice. The fourth chapter is joint work with Federico Echenique and Kota Saito. We develop an axiomatic theory of random choice that builds on Luce's (1959) model to incorporate a role for perception. We capture the role of perception through perception priorities; priorities that determine whether an object or alternative is perceived sooner or later than other alternatives. We identify agents' perception priorities from their violations of Luce's axiom of independence from irrelevant alternatives (IIA). The direction of the violation of IIA implies an orientation of agents' priority rankings. We adjust choice probabilities to account for the effects of perception, and impose that adjusted choice probabilities satisfy IIA. So all violations of IIA are accounted for by the perception order. The theory can explain some very well-documented behavioral phenomena in individual choice. We can also explain the effects of forced choice and choice overload in experiments. The fifth chapter studies how the ordering of alternatives (e.g., the location of products in a grocery store, the order of candidates on a ballot) affects a decision maker's choices. I develop an axiomatic model of random choice that builds on Luce's (1959) and incorporates the effect of the ordering of alternatives on choice frequencies. When the ordering of alternatives is observed, I characterize the model by two weakenings of IIA. When the ordering of alternatives is not observed, I can identify it from choice data. The model can accommodate the similarity, compromise, and attraction effects, violations of stochastic transitivity, and the choice overload, which are well-known behavioral phenomena in individual choice.</p