62 research outputs found

    Essays on Individual Choice and Behavior

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    This dissertation consists of three chapters that explore individual choice and behavior. Chapter 1 investigates the incentive properties of advisory referenda using a particular form of NEU theory which replaces the independence axiom assumed in EU theory with two less-restrictive assumptions: betweenness and fanning-out. Betweenness replaces the independence axiom and allows for context dependent risk attitudes. The fanning-out hypothesis then governs the precise way in which risk preferences change given the unique circumstances in which values are elicited. When the assumption of independence is relaxed, an individual\u27s response to an advisory referendum depends on how consequential she believes her response to be, and her beliefs regarding the existence of alternative proposals. Chapter 2 utilizes laboratory experiments to investigate the behavioral dynamics pertaining to information acquisition and tax evasion. In recent years, a service paradigm, whereby tax authorities provide information about correct tax reporting to taxpayers, has shown the potential to further encourage correct tax reporting. The results show that the overall effect of a helpful information service is to decrease tax evasion. Further, an audit has the behavioral effect of lowering information acquisition rates and increasing evasion immediately after experiencing a penalty. This effect persists (although diminishes) in subsequent tax reporting decisions. Chapter 3 builds upon the existing experimental literature regarding ``decoy effects” through an innovative design, which preserved the fundamental features of a consumer choice setting in the laboratory. The design involves choices with financial consequences, real consumer goods, and the ability for participants to opt-out. Through the novel experimental approach and econometric analysis, we demonstrate that the decoy effect is not an artifact of hypothetical settings, the decoy effect is not driven by forced choice, and that decoys do little more than sway individuals at the point of indifference

    Social Networks and Non-market Valuations *

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    Abstract This paper considers the role of social networks in the non-market valuation of public goods. In the model individuals derive utility from both their own direct enjoyment of the public good as well as from the enjoyment of those in their network. We find that network structure almost always matters, both for utility and for valuation. The network increases aggregate valuation when it assigns higher importance, that is, greater total weight, to individuals with higher private values for the public good. The model provides a theoretical foundation for the idea of opinion leaders who have disproportionate influence over their communities. Specifically, opinion leaders are individuals assigned high importance by the network, and projects favored by opinion leaders tend to be favored by the network as a whole. The model can also guide future empirical studies by enabling a more structural approach to non-market valuation in a socially-connected group

    Terminal uranium(V/VI) nitride activation of carbon dioxide and carbon disulfide: factors governing diverse and well-defined cleavage and redox reactions

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    The reactivity of terminal uranium(V/VI) nitrides with CE2 (E=O, S) is presented. Well-defined C=E cleavage followed by zero-, one-, and two-electron redox events is observed. The uranium(V) nitride [U(TrenTIPS)(N)][K(B15C5)2] (1, TrenTIPS=N(CH2CH2NSiiPr3)3; B15C5=benzo-15-crown-5) reacts with CO2 to give [U(TrenTIPS)(O)(NCO)][K(B15C5)2] (3), whereas the uranium(VI) nitride [U(TrenTIPS)(N)] (2) reacts with CO2 to give isolable [U(TrenTIPS)(O)(NCO)] (4); complex 4 rapidly decomposes to known [U(TrenTIPS)(O)] (5) with concomitant formation of N2 and CO proposed, with the latter trapped as a vanadocene adduct. In contrast, 1 reacts with CS2 to give [U(TrenTIPS)(Îș2-CS3)][K(B15C5)2] (6), 2, and [K(B15C5)2][NCS] (7), whereas 2 reacts with CS2 to give [U(TrenTIPS)(NCS)] (8) and “S”, with the latter trapped as Ph3PS. Calculated reaction profiles reveal outer-sphere reactivity for uranium(V) but inner-sphere mechanisms for uranium(VI); despite the wide divergence of products the initial activation of CE2 follows mechanistically related pathways, providing insight into the factors of uranium oxidation state, chalcogen, and NCE groups that govern the subsequent divergent redox reactions that include common one-electron reactions and a less-common two-electron redox event. Caution, we suggest, is warranted when utilising CS2 as a reactivity surrogate for CO2

    Reduction Chemistry of Neptunium cyclopentadienide complexes: from structure to understanding

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    Neptunium complexes in the formal oxidation states II, III, and IV supported by cyclopentadienyl ligands are explored, and significant differences between Np and U highlighted as a result. A series of neptunium(III) cyclopentadienyl (Cp) complexes [Np(Cp)3], its bis-acetonitrile adduct [Np(Cp)3(NCMe)2], plus its KCp adduct K[Np(Cp)4] and [Np(Cp')3] (Cp' = C5H4SiMe3) have been made and characterised providing the first single crystal x-ray analyses of NpIII Cp complexes. In all NpCp3 derivatives there are three Cp rings in eta5-coordination around the NpIII centre; additionally in [Np(Cp)3] and K[Np(Cp)4] one Cp ring establishes a mu-eta1-interaction to one C atom of a neighbouring NpCp3 unit. The solid state structure of K[NpCp4] is unique in containing two different types of metal-Cp coordination geometries in the same crystal. NpIIICp4 units are found exhibiting four units of eta5-coordinated Cp rings like in the known complex [NpIV(Cp)4], the structure of which is now reported. A detailed comparison of the structures gives evidence for the change of ionic radii of ca. -8 pm associated with change in oxidation state between NpIII and NpIV. The rich redox chemistry associated with the syntheses is augmented by the reduction of [Np(Cp')3] by KC8 in the presence of 2.2.2 cryptand to afford the putative neptunium(II) K(2.2.2 cryptand)[Np(Cp')3] that is thermally unstable above -10 °C like its U and Th congeners. Together, these spontaneous and controlled redox reactions of organo-neptunium complexes, along with information from structural characterisation, show the relevance of organometallic Np chemistry to understanding fundamental structure and bonding in the minor actinides.JRC.G.I.5-Advanced Nuclear Knowledg

    Mixed sandwich imido complexes of Uranium(V) and Uranium(IV): Synthesis, structure and redox behaviour

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    The mixed sandwich U(III) complex {U[η ^8 -C8H6(1,4-Si( iPr)3)2](Cp*)(THF)} reacts with the organic azides RN3 (R = SiMe3, 1-Ad, BMes2) to afford the corresponding, structurally characterised U(V) imido complexes {U[η ^8 -C8H6(1,4-Si( iPr)3)2](Cp*)(NR)}. In the case of R=SiMe3, the reducing power of the U(III) complex leads to reductive coupling as a parallel minor reaction pathway, forming R-R and the U(IV) azide-bridged complex{[U]}2(”-N3)2, along with the expected [U]=NR complex. All three [U] =NR complexes show a quasi-reversible one electron reduction between -1.6 to -1.75 V, and for R= SiMe3, chemical reduction using K/Hg affords the anionic U(IV) complex K+ {U[η ^8 -C8H6(1,4-Si( iPr)3)2](Cp*)=NSiMe3} - . The molecular structure of the latter shows an extended structure in the solid state in which the K counter cations are successively sandwiched between the Cp* ligand of one [U] anion and the COTtips2 ligand of the next

    Actinide covalency measured by pulsed electron paramagnetic resonance spectroscopy

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    Our knowledge of actinide chemical bonds lags far behind our understanding of the bonding regimes of any other series of elements. This is a major issue given the technological as well as fundamental importance of f-block elements. Some key chemical differences between actinides and lanthanides—and between different actinides—can be ascribed to minor differences in covalency, that is, the degree to which electrons are shared between the f-block element and coordinated ligands. Yet there are almost no direct measures of such covalency for actinides. Here we report the first pulsed electron paramagnetic resonance spectra of actinide compounds. We apply the hyperfine sublevel correlation technique to quantify the electron-spin density at ligand nuclei (via the weak hyperfine interactions) in molecular thorium(III) and uranium(III) species and therefore the extent of covalency. Such information will be important in developing our understanding of the chemical bonding, and therefore the reactivity, of actinides

    The Renaissance of Non-Aqueous Uranium Chemistry

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    Re-pair for Trees

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    We introduce a new linear time compression algorithm, called 'Repair for Trees', which compresses ordered trees over a ranked alphabet using linear straight-line context-free tree grammars. Such grammars generalize straight-line context-free string grammars and allow basic tree operations, like traversal along edges, to be executed without prior decompression. Our algorithm can be considered as a generalization of the 'Re-pair' algorithm developed by N. Jesper Larsson and Alistair Moffat in 2000. The latter algorithm is a dictionary-based compression algorithm for strings. We also introduce a succinct coding which is specialized in further compressing the grammars generated by our algorithm. Thisis accomplished without loosing the ability do directly execute queries on this compressed representation of the input tree. Finally, we compare the grammars and output files generated by a prototype of the Re-pair for Trees algorithm with those of similar compression algorithms. The obtained results show that that our algorithm outperforms its competitors in terms of compression ratio, runtime and memory usage
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