bluuebunny/crossref_metadata_2025 huggingface dataset:
Determinacy and the sharp function on objects of type k
Authors: Dubose Derrick Albert
Published: May 2006

We characterize, in terms of determinacy, the existence of the least inner model of “every object of type k has a sharp.” For k ∈ ω, we define two classes of sets, and , which lie strictly between and . Let #k be the (partial) sharp function on objects of type k. We show that the determinacy of follows from

L[#k] ⊨ “every object of type k has a sharp”,

and we show that the existence of indiscemibles for L[#k] is equivalent to a slightly stronger determinacy hypothesis, the determinacy of .
The axiom of choice for well-ordered families and for families of well-orderable sets
Authors: Howard Paul , Rubin Jean E.
Published: May 2006

We show that it is not possible to construct a Fraenkel-Mostowski model in which the axiom of choice for well-ordered families of sets and the axiom of choice for sets of well-orderable sets are both true, but the axiom of choice is false.
Amoeba reals
Authors: Judah Haim , Repickẏ Miroslav
Published: May 2006

We define the ideal with the property that a real omits all Borel sets in the ideal which are coded in a transitive model if and only if it is an amoeba real over this model. We investigate some other properties of this ideal. Strolling through the "amoeba forest" we gain as an application a modification of the proof of the inequality between the additivities of Lebesgue measure and Baire category.
On reduction properties
Authors: Kikyo Hirotaka , Tsuboi Akito
Published: May 2006

Let us consider countable languages L containing a unary predicate symbol P and L− =L\{P}. We also assume that L is relational. Then for any L-structure M, N = PM can naturally be considered as an L−-substructure of M. The main object of this paper will be the study of the following question: Under what condition does M have to be ℵ0-categorical. ℵ1-categorical, or stable if N is?

Hodges and Pillay [6] proved that if M is a countable symmetric extension of N and T = Th(M) is minimal over P (they said that T is one-cardinal over P), then the total categoricity of N implies that of M. This is a solution to a problem in Ahlbrandt and Ziegler [1]. The condition that “M is a symmetric extension of N” is an interpretation of the condition “every relation on N definable in M is definable within N”. We shall give several interpretations of this phrase: They are the Ø-reduction property, the reduction property, the strong reduction property, and the uniform reduction property (Definition 1). Under the assumptions, we study the question proposed above.

In §3 we treat the case that M is countable and show that if T is minimal over P and M has the strong reduction property over N, then M is ℵ0-categorical if N is (Theorem 5). This is a slight extension of the result of Hodges and Pillay mentioned above. (If M is countable and saturated, then the strong reduction property is equivalent to the condition that M will be symmetric over N if we add a finite number of appropriate constants.) A counterexample to this theorem has been obtained by Hrushovski in the case that only the Ø-reduction property is assumed. We also give a stronger result: If M has the Ø-reduction property over N and is ℵ0-categorical, M\N is infinite, and N is algebraically closed, then there is an expansion M* of M such that M* is not ℵo-categorical but M* still has the Ø-reduction property over N (Theorem 6). Moreover, we give an example such that M has the uniform reduction property over N. Th(M*) is minimal over P. N is ℵ0-categorical but M is not.
Flat sets
Authors: Grainger Arthur D.
Published: May 2006

Let X be a set, and let be the superstructure of X, where X0 = X and is the power set of X) for n ∈ ω. The set X is called a flat set if and only if for each x ∈ X, and x ∩ ŷ = ø for x, y ∈ X such that x ≠ y. where is the superstructure of y. In this article, it is shown that there exists a bijection of any nonempty set onto a flat set. Also, if is an ultrapower of (generated by any infinite set I and any nonprincipal ultrafilter on I), it is shown that is a nonstandard model of X: i.e., the Transfer Principle holds for and , if X is a flat set. Indeed, it is obvious that is not a nonstandard model of X when X is an infinite ordinal number. The construction of flat sets only requires the ZF axioms of set theory. Therefore, the assumption that X is a set of individuals (i.e., x ≠ ϕ and a ∈ x does not hold for x ∈ X and for any element a) is not needed for to be a nonstandard model of X.
The finite model property for various fragments of intuitionistic linear logic
Authors: Okada Mitsuhiro , Terui Kazushige
Published: May 2006

Recently Lafont [6] showed the finite model property for the multiplicative additive fragment of linear logic (MALL) and for affine logic (LLW), i.e., linear logic with weakening. In this paper, we shall prove the finite model property for intuitionistic versions of those, i.e. intuitionistic MALL (which we call IMALL), and intuitionistic LLW (which we call ILLW). In addition, we shall show the finite model property for contractive linear logic (LLC), i.e., linear logic with contraction. and for its intuitionistic version (ILLC). The finite model property for related substructural logics also follow by our method. In particular, we shall show that the property holds for all of FL and GL−-systems except FLc and of Ono [11], that will settle the open problems stated in Ono [12].
Unification in intuitionistic logic
Authors: Ghilardi Silvio
Published: May 2006

We show that the variety of Heyting algebras has finitary unification type. We also show that the subvariety obtained by adding it De Morgan law is the biggest variety of Heyting algebras having unitary unification type. Proofs make essential use of suitable characterizations (both from the semantic and the syntactic side) of finitely presented projective algebras.
Recursive in a generic real
Authors: Shinoda Juichi , Slaman Theodore A.
Published: May 2006

There is a comeager set contained in the set of 1-generic reals and a first order structure such that for any real number X. there is an element of which is recursive in X if and only if there is a presentation of which is recursive in X.
Filters, Cohen sets and consistent extensions of the Erdős-Dushnik-Miller Theorem
Authors: Shelah Saharon , Stanley Lee J.
Published: May 2006

We present two different types of models where, for certain singular cardinals λ of uncountable cofinality, λ → (λ, ω + 1)2, although λ is not a strong limit cardinal, We announce, here, and will present in a subsequent paper, [7], that, for example, consistently,and consistently,.
New techniques and completeness results for preferential structures
Authors: Schlechta Karl
Published: May 2006

Preferential structures are probably the best examined semantics for nonmonotonic and deontic logics: in a wider sense, they also provide semantical approaches to theory revision and update, and other fields where a preference relation between models is a natural approach. They have been widely used to differentiate the various systems of such logics, and their construction is one of the main subjects in the formal investigation of these logics. We introduce new techniques to construct preferential structures for completeness proofs. Since our main interest is to provide general techniques, which can be applied in various situations and for various base logics (propositional and other), we take a purely algebraic approach, which can be translated into logics by easy lemmata, in particular, we give a clean construction via indexing by trees for transitive structures, this allows us to simplify the proofs of earlier work by the author, and to extend the results given there.
Equivalence elementaire et decidabilite pour des structures du type groupe agissant sur un groupe abelien
Authors: Simonetta Patrick
Published: May 2006

We prove an Ax-Kochen-Ershov like transfer principle for groups acting on groups. The simplest case is the following: let B be a soluble group acting on an abelian group G so that G is a torsion-free divisible module over the group ring ℤ[B], then the theory of B determines the one of the two-sorted structure 〈G,B,*〉, where * is the action of B on C. More generally, we show a similar principle for structures 〈G,B,*〉, where G is a torsion-free divisible module over the quotient of ℤ[B] by the annulator of G.

Two applications come immediately from this result:

First, for not necessarily commutative domains, where we consider the action of a subgroup of the invertible elements on the additive group. We obtain then the decidability of a weakened structure of ring, with partial multiplication.

The second application is to pure groups. The semi-direct product of G by B is bi-interpretable with our structure 〈G,B,*〉. Thus, we obtain stable decidable groups that are not linear over a field.
The determinacy of Blackwell games
Authors: Martin Donald A.
Published: May 2006

Games of infinite length and perfect information have been studied for many years. There are numerous determinacy results for these games, and there is a wide body of work on consequences of their determinacy.

Except for games with very special payoff functions, games of infinite length and imperfect information have been little studied. In 1969, David Blackwell [1] introduced a class of such games and proved a determinacy theorem for a subclass. During the intervening time, there has not been much progress in proving the determinacy of Blackwell's games. Orkin [17] extended Blackwell's result to a slightly wider class. Blackwell [2] found a new proof of his own result. Maitra and Sudderth [9, 10] improved Blackwell's result in a different direction from that of Orkin and also generalized to the case of stochastic games. Recently Vervoort [18] has obtained a substantial improvement. Nevertheless, almost all the basic questions have remained open.

In this paper we associate with each Blackwell game a family of perfect information games, and we show that the (mixed strategy) determinacy of the former follows from the (pure strategy) determinacy of the latter. The complexity of the payoff function for the Blackwell game is approximately the same as the complexity of the payoff sets for the perfect information games. In particular, this means that the determinacy of Blackwell games with Borel measurable payoff functions follows from the known determinacy of perfect information games with Borel payoff sets.
Fragments of Heyting arithmetic
Authors: Burr Wolfgang
Published: May 2006

We define classes Φnof formulae of first-order arithmetic with the following properties:

(i) Everyφϵ Φnis classically equivalent to a Πn-formula (n≠ 1, Φ1:= Σ1).

(ii)

(iii)IΠnandiΦn(i.e., Heyting arithmetic with induction schema restricted to Φn-formulae) prove the same Π2-formulae.

We further generalize a result by Visser and Wehmeier. namely that prenex induction within intuitionistic arithmetic is rather weak: After closing Φnboth under existential and universal quantification (we call these classes Θn) the corresponding theoriesiΘnstill prove the same Π2-formulae. In a second part we consideriΔ0plus collection-principles. We show that both the provably recursive functions and the provably total functions ofare polynomially bounded. Furthermore we show that the contrapositive of the collection-schema gives rise to instances of the law of excluded middle and hence.
On decidable extensions of Presburger arithmetic: from A. Bertrand numeration sytems to Pisot numbers
Authors: Point Françoise
Published: May 2006

We study extensions of Presburger arithmetic with a unary predicate R and we show that under certain conditions on R, R is sparse (a notion introduced by A. L. Semënov) and the theory of 〈ℕ, +, R〉 is decidable. We axiomatize this theory and we show that in a reasonable language, it admits quantifier elimination. We obtain similar results for the structure 〈ℚ, +, R〉.
Forcing on bounded arithmetic II
Authors: Takeuti Gaisi , Yasumoto Masahiro
Published: May 2006

Forcing method on Bounded Arithmetic was first introduced by J. B. Paris and A. Wilkie in [10]. Then in [1], [2] and [3], M. Ajtai used the method to get excellent results on the pigeon hole principle and the modulo p counting principle. The forcing method on Bounded arithmetic was further developed by P. Beame, J. Krajíček and S. Riis in [4], [7], [6], [8], [5], [12], [11], [13]. It should be noted that J. Krajíček and P. Pudlák used an idea of Boolean valued in [9] and also Boolean valued notion is efficiently used for model theoretic constructions in [7], [6], [8], [5].

In our previous paper [14], we developed a Boolean valued version of forcing on Bounded Arithmetic using Boolean algebra which is generated by polynomial size circuits from Boolean variables and discussed its relation with NP = co-NP problem and P = NP problem. Especially we proved the following theorem and related theorems as Theorems 2, 3 and 4 in Section 2.

Theorem. If M[G] is not a model of S2, then NP ≠ co-NP and therefore P ≠ NP.

However in the proof of the Theorem, we used a consequence of P = NP. More precisely we used the following as a consequence of NP = co-NP, though it is a consequence of P = NP but not a consequence of NP = co-NP.

Suppose that NP = co-NP holds. Then there exists an NP-complete predicate ∃x ≤ t(a) A(x,a) with sharply bounded A(x, a) and a sharply bounded B(y, a) such that ∃x ≤ t(a) A(x,a) ↔ ∀y ≤ s(a)B(y, a). Then there exists polynomial time computable functions f and g such that the following two sequents hold.
On automorphism groups of countable structures
Authors: Gao Su
Published: May 2006

Strengthening a theorem of D. W. Kueker, this paper completely charaterizes which countable structures do not admit uncountable Lω1ω-elementarily equivalent models. In particular, it is shown that if the automorphism group of a countable structure M is abelian, or even just solvable, then there is no uncountable model of the Scott sentence of M. These results arise as part of a study of Polish groups with compatible left-invariant complete metrics.
Rado's conjecture and presaturation of the nonstationary ideal on ω1
Authors: Feng Qi
Published: May 2006

We prove that Rado's Conjecture implies that the nonstationary ideal on ω1 is presaturated.
Geometry of *-Finite Types
Authors: Newelski Ludomir
Published: May 2006

AssumeTis a superstable theory with < 2ℵ0countable models. We prove that any *- algebraic type of-rank > 0 is m-nonorthogonal to a *-algebraic type of-rank 1. We study the geometry induced by m-dependence on a *-algebraic typep*of-rank 1. We prove that after some localization this geometry becomes projective over a division ring. Associated withp*is a meager typep. We prove thatpis determined byp*up to nonorthogonality and thatunderlies also the geometry induced by forking dependence on any stationarization ofp. Also we study some *-algebraic *-groups of-rank 1 and prove that any *-algebraic *-group of-rank 1 is abelian-by-finite.
Stable models and reflexive banach spaces
Authors: Iovino José
Published: May 2006

We show that a formula φ(x, y) is stable if and only if φ is the pairing map on the unit ball of E × E*, where E is a reflexive Banach space. The result remains true if the formula φ is replaced by a set of formulas .
Free set algebras satisfying systems of equations
Authors: Antonelli G. Aldo
Published: May 2006

In this paper we introduce the notion of a set algebra satisfying a system E of equations. After defining a notion of freeness for such algebras, we show that, for any system E of equations, set algebras that are free in the class of structures satisfying E exist and are unique up to a bisimulation. Along the way, analogues of classical set-theoretic and algebraic properties are investigated.
Pseudo-finite homogeneity and saturation
Authors: Flum Jörg , Ziegler Martin
Published: May 2006

When analyzing database query languages a roperty, of theories, the pseudo-finite homogeneity property, has been introduced and applied (cf. [3]). We show that a stable theory has the pseudo-finite homogeneity property just in case its expressive power for finite states is bounded. Moreover, we introduce the corresponding pseudo-finite saturation property and show that a theory fails to have the finite cover property if and only if it has the pseudo-finite saturation property.
On the Restraining Power of Guards
Authors: Grädel Erich
Published: May 2006

Guarded fragments of first-order logic were recently introduced by Andréka, van Benthem and Németi; they consist of relational first-order formulae whose quantifiers are appropriately relativized by atoms. These fragments are interesting because they extend in a natural way many propositional modal logics, because they have useful model-theoretic properties and especially because they are decidable classes that avoid the usual syntactic restrictions (on the arity of relation symbols, the quantifier pattern or the number of variables) of almost all other known decidable fragments of first-order logic.

Here, we investigate the computational complexity of these fragments. We prove that the satisfiability problems for the guarded fragment (GF) and the loosely guarded fragment (LGF) of first-order logic are complete for deterministic double exponential time. For the subfragments that have only a bounded number of variables or only relation symbols of bounded arity, satisfiability is Exptime-complete. We further establish a tree model property for both the guarded fragment and the loosely guarded fragment, and give a proof of the finite model property of the guarded fragment.

It is also shown that some natural, modest extensions of the guarded fragments are undecidable.
Undecidable extensions of Skolem arithmetic
Authors: Bès Alexis , Richard Denis
Published: May 2006

Let be the restriction of usual order relation to integers which are primes or squares of primes, and let ⊥ denote the coprimeness predicate. The elementary theory of is undecidable. Now denote by <π the restriction of order to primary numbers. All arithmetical relations restricted to primary numbers are definable in the structure (ℕ; ⊥, <π). Furthermore, the structures (ℕ; ∣, <π) (ℕ; =, ×, <π) and (ℕ; =, +, ×) are interdefinable.
Explicit mathematics with the monotone fixed point principle
Authors: Rathjen Michael
Published: May 2006

The context for this paper is Feferman's theory of explicit mathematics, a formal framework serving many purposes. It is suitable for representing Bishop-style constructive mathematics as well as generalized recursion, including direct expression of structural concepts which admit self-application. The object of investigation here is the theory of explicit mathematics augmented by the monotone fixed point principle, which asserts that any monotone operation on classifications (Feferman's notion of set) possesses a least fixed point. To be more precise, the new axiom not merely postulates the existence of a least solution, but, by adjoining a new functional constant to the language, it is ensured that a fixed point is uniformly presentable as a function of the monotone operation.

The upshot of the paper is that the latter extension of explicit mathematics (when based on classical logic) embodies considerable proof-theoretic strength. It is shown that it has at least the strength of the subsystem of second order arithmetic based on comprehension.
A note on valuation definable expansions of fields
Authors: Haskell Deirdre , Dugald Macpherson
Published: May 2006

In this note, we consider models of the theories of valued algebraically closed fields and convexly valued real closed fields, their reducts to the pure field or ordered field language respectively, and expansions of these by predicates which are definable in the valued field. We show that, in terms of definability, there is no structure properly between the pure (ordered) field and the valued field. Our results are analogous to several other definability results for reducts of algebraically closed and real closed fields; see [9], [10], [11] and [12]. Throughout this paper, definable will mean definable with parameters.

Theorem A. Let ℱ = (F, +, ×, V) be a valued, algebraically closed field, where V denotes the valuation ring. Let A be a subset ofFndefinable in ℱv. Then either A is definable in ℱ = (F, +, ×) or V is definable in.

Theorem B. Let ℛv = (R, <, +, ×, V) be a convexly valued real closed field, where V denotes the valuation ring. Let Abe a subset ofRndefinable in ℛv. Then either A is definable in ℛ = (R, <, +, ×) or V is definable in.

The proofs of Theorems A and B are quite similar. Both ℱv and ℛv admit quantifier elimination if we adjoin a definable binary predicate Div (interpreted by Div(x, y) if and only if v(x) ≤ v(y)). This is proved in [14] (extending [13]) in the algebraically closed case, and in [4] in the real closed case. We show by direct combinatorial arguments that if the valuation is not definable then the expanded structure is strongly minimal or o-minimal respectively. Then we call on known results about strongly minimal and o-minimal fields to show that the expansion is not proper.
Undecidable theories of Lyndon algebras
Authors: Stebletsova Vera , Venema Yde
Published: May 2006

With each projective geometry we can associate a Lyndon algebra. Such an algebra always satisfies Tarski's axioms for relation algebras and Lyndon algebras thus form an interesting connection between the fields of projective geometry and algebraic logic. In this paper we prove that if G is a class of projective geometries which contains an infinite projective geometry of dimension at least three, then the class L(G) of Lyndon algebras associated with projective geometries in G has an undecidable equational theory. In our proof we develop and use a connection between projective geometries and diagonal-free cylindric algebras.
Cohen reals from small forcings
Authors: Pawlikowski Janusz
Published: May 2006

We introduce a new cardinal characteristic r*. related to the reaping number r. and show that

• posets of size < r* which add reals add unbounded reals;

• posets of size < r which add unbounded reals add Cohen reals.

We also show that add() ≤ min(r. r*). It follows that posets of size < add() which add reals add Cohen reals.

This improves results of Roslanowski and Shelah [RS] and of Zapletal [Z].
Existentially closed structures and Gödel's second incompleteness theorem
Authors: Adamowicz Zofia , Bigorajska Teresa
Published: May 2006

We prove that any 1-closed (see def 1.1) model of the Π2 consequences of PA satisfies ¬Cons PA which gives a proof of the second Gödel incompleteness theorem without the use of the Gödel diagonal lemma. We prove a few other theorems by the same method.
Some structural results concerning supercompact cardinals
Authors: Apter Arthur W.
Published: May 2006

We show how the forcing of [5] can be iterated so as to get a model containing supercompact cardinals in which every measurable cardinal δ is δ+ supercompact. We then apply this iteration to prove three additional theorems concerning the structure of the class of supercompact cardinals.
Free ordered algebraic structures towards proof theory
Authors: Prijatelj Andreja
Published: May 2006

In this paper, constructions of free ordered algebras on one generator are given that correspond to some one-variable fragments of affine propositional classical logic and their extensions with n-contraction (n ≥ 2). Moreover, embeddings of the already known infinite free structures into the algebras introduced below are furnished with; thus, solving along the respective cardinality problems.
Polarized partition relations
Authors: Baumgartner James E. , Hajnal Andras
Published: May 2006

It is shown that for any cardinalκ,, and ifκis weakly compact then.
Simplicity, and stability in there
Authors: Kim Byunghan
Published: May 2006

Firstly, in this paper, we prove that the equivalence of simplicity and the symmetry of forking. Secondly, we attempt to recover definability part of stability theory to simplicity theory. In particular, using elimination of hyperimaginaries we prove that for any supersimpleT. canonical base of an amalgamation classis the union of names ofψ-definitions of,ψranging over stationaryL-formulas in. Also, we prove that the same is true with stable formulas for an 1-based theory having elimination of hyperimaginaries. For such a theory, the stable forking property holds, too.
Ramsey's theorem for computably enumerable colorings
Authors: Hummel Tamara J. , Jockusch Carl G.
Published: May 2006

It is shown that for each computably enumerable set of n-element subsets of ω there is an infinite set A ⊆ ω such that either all n-element subsets of A are in or no n-element subsets of A are in . An analogous result is obtained with the requirement that A be replaced by the requirement that the jump of A be computable from 0(n). These results are best possible in various senses.
Identity crises and strong compactness
Authors: Apter Arthur W. , Cummings James
Published: May 2006

Combining techniques of the first author and Shelah with ideas of Magidor, we show how to get a model in which, for fixed but arbitrary finite n, the first n strongly compact cardinals k1..…kn are so that ki; for i = 1..…n is both the ith measurable cardinal and supercompact. This generalizes an unpublished theorem of Magidor and answers a question of Apter and Shelah.
An axiomatization of full Computation Tree Logic
Authors: Reynolds M.
Published: May 2006

We give a sound and complete axiomatization for the full computation tree logic. CTL*, of R-generable models. This solves a long standing open problem in branching time temporal logic.
First order theories for nonmonotone inductive definitions: recursively inaccessible and Mahlo
Authors: Jäger Gerhard
Published: May 2006

In this paper first order theories for nonmonotone inductive definitions are introduced, and a proof-theoretic analysis for such theories based on combined operator forms à la Richter with recursively inaccessible and Mahlo closure ordinals is given.
Existence of prime elements in rings of generalized power series
Authors: Pitteloud Daniel
Published: May 2006

The fieldK((G)) of generalized power series with coefficients in the fieldKof characteristic 0 and exponents in the ordered additive abelian groupGplays an important role in the study of real closed fields. Conway and Gonshor (see [2, 4]) considered the problem of existence of non-standard irreducible (respectively prime) elements in the huge “ring” of omnific integers, which is indeed equivalent to the existence of irreducible (respectively prime) elements in the ringK((G≤0)) of series with non-positive exponents. Berarducci (see [1]) proved thatK((G≤0)) does have irreducible elements, but it remained open whether the irreducibles are prime i.e., generate a prime ideal. In this paper we prove thatK((G≤0)) does have prime elements ifG= (ℝ, +) is the additive group of the reals, or more generally ifGcontains a maximal proper convex subgroup.
Main gap for locally saturated elementary submodels of a homogeneous structure
Authors: Hyttinen Tapani , Shelah Saharon
Published: May 2006

We prove a main gap theorem for locally saturated submodels of a homogeneous structure. We also study the number of locally saturated models, which are not elementarily embeddable into each other.
The cofinality of the random graph
Authors: Warner Steve
Published: May 2006

We show that under Martin's Axiom, the cofinalitycf(Aut(Γ)) of the automorphism group of the random graph Γ is 2ω.
Endogenous Preferences and the Study of Institutions
Authors: Gerber Elisabeth R. , Jackson John E.
Published: May 2006

The assumption that individual preferences, or attitudes, are fixed and exogenously determined is central to many studies of political and economic institutions, such as markets and elections. We present a Bayesian model of adaptive preferences and empirical evidence consistent with that model to argue that preferences are not always exogenous and fixed. The changing relationships between partisanship and preferences on civil rights issues between 1956 and 1964 and on the Vietnam War issue between 1968 and 1972 coincide with significant changes in the major parties' positions on these issues, suggesting that preferences are endogenous to the electoral process. We conclude with a discussion of the positive and normative implications of endogenous preferences.
The Effectiveness of Antiterrorism Policies: A Vector-Autoregression-Intervention Analysis
Authors: Enders Walter , Sandler Todd
Published: May 2006

Using quarterly data from 1968 to 1988, we analyze the time series properties of the various attack modes used by transnational terrorists. Combining vector autoregression and intervention analysis, we find strong evidence of both substitutes and complements among the attack modes. We also evaluate the effectiveness of six policies designed to thwart terrorism. The existence of complements and substitutes means that policies designed to reduce one type of attack may affect other attack modes. For example, the installation of metal detectors in airports reduced skyjackings and diplomatic incidents but increased other kinds of hostage attacks (barricade missions, kidnappings) and assassinations. In the long run, embassy fortification decreased barricade missions but increased assassinations. The Reagan “get tough” policy, which resulted in the enactment of two laws in 1984 and a retaliatory raid on Libya in 1986, did not have any noticeable long-term effect on curbing terrorist attacks directed against U.S. interests.
The British Election
Authors: Graper Elmer D.
Published: May 2006

After experimenting with coalitions and with a minority Labor government, the voters of Great Britain on October 29, in their third general election in two years, returned the Conservative party to power with a large majority over the combined opposition groups. Thus the traditional system of party government was restored. The desire for stability and the fear of fundamental changes in the political and economic order were probably the chief causes of the overwhelming Conservative victory.
Political Science in Great Britain and France
Authors: Laski Harold J. , Caudel Maurice
Published: May 2006

In response to requests for information concerning recent developments in political science in Great Britain and France, the following accounts were received from Professor Harold J. Laski, of the London School of Economics and Political Science, and M. Maurice Caudel, of L'École Libre des Sciences Politiques and editor of the Revue des Sciences Politiques:

Great Britain. It will be well-known to American students of political science, especially since Professor Fairlie's very careful survey in a previous number of the Political Science Review, that there is practically no organized study of political science in Great Britain.
Government Formation and Endogenous Parties
Authors: Baron David P.
Published: May 2006

I provide a formal theory of government for a political system characterized by a proportional representation electoral system, a parliamentary government that exercises collective responsibility, and a government formation process. Political parties are assumed to be policy-oriented and to serve the interests of those who vote for them. Parties choose policy platforms that determine their representation in parliament; and given that representation, the parties bargain over the government to be formed and the policies that government will implement. The model yields equilibria with the property that parties choose dispersed policy positions. Thus, electoral incentives in proportional representation parliamentary systems need not lead to policy convergence. The theory provides predictions of party locations such as those developed in the manifesto project.
Polarity and International Stability
Authors: Midlarsky Manus I. , Hopf Ted
Published: May 2006

In his article in the June 1991 issue of thisReview, Ted Hopf challenged the argument that bipolar systems are inherently more stable than multipolar configurations of power. He reported that the international situation in sixteenth century Europe became only marginally more stable with a shift from a multipolar to a bipolar system. He argued for attention to the offensive-defensive balance, rather than systemic polarity. Manus Midlarsky accounts for Hopf's findings, and for evidence of multipolarity and increased conflict in the early seventeenth and twentieth centuries, by proposing a relationship between polarity and war that is contingent on scarcity of desired international resources. Midlarsky argues for more attention to contingent relationships generally and draws implications for current and future probabilities of conflict in a multipolar world. Hopf responds by pointing out the need for further development of Midlarsky's analysis, the possible compatibility between Midlarsky's formulation and his own focus on the offensive-defensive balance, and the desirability of a productive unity of the two research programs.
Messages Received: The Political Impact of Media Exposure
Authors: Bartels Larry M.
Published: May 2006

Analyses of the persuasive effects of media exposure outside the laboratory have generally produced negative results. I attribute such nonfindings in part to carelessness regarding the inferential consequences of measurement error and in part to limitations of research design. In an analysis of opinion change during the 1980 presidential campaign, adjusting for measurement error produces several strong media exposure effects, especially for network television news. Adjusting for measurement error also makes preexisting opinions look much more stable, suggesting that the new information absorbed via media exposure must be about three times as distinctive as has generally been supposed in order to account for observed patterns of opinion change.
The Politics of Virtue Today: A Critique and a Proposal
Authors: Burtt Shelley
Published: May 2006

I argue for a distinction between publicly oriented and privately oriented conceptions of civic virtue. I first provide a critique of two current politics of virtue (liberal and republican), arguing (1) that despite their differences, they are both publicly oriented and (2) that their problems lie in this public orientation. I conclude by arguing for the legitimacy and promise of a privately oriented politics of civic virtue, using as examples of this approachCato's Lettersfrom the early eighteenth century and the work of two contemporary theorists, Bruce Ackerman and Stephen Elkin.
Reassessing Mass Support for Political and Economic Change in the Former USSR
Authors: Miller Arthur H. , Hesli Vicki L. , Reisinger William M.
Published: May 2006

Using survey data collected in Russia, Ukraine, and Lithuanian in 1990–92, we reexamine findings reported by Finifter and Mickiewicz (1992). Our analysis indicates a significant link between political and economic reform orientations. Individuals who prefer political reforms of a democratic nature also favor a decreased role of the state in guaranteeing social well-being. In addition, our finding that better-educated Soviet and post-Soviet citizens are more likely than the less-well-educated to prefer individual responsibility for well-being is in direct contradiction to the findings reported by Finifter and Mickiewicz. The differences in the two sets of conclusions give rise to very different substantive conclusions regarding the economic and political changes now occurring in these societies.
Shortcuts Versus Encyclopedias: Information and Voting Behavior in California Insurance Reform Elections
Authors: Lupia Arthur
Published: May 2006

Voters in mass elections are notorious for their apparent lack of information about relevant political matters. While some scholars argue that an electorate of well-informed voters is necessary for the production of responsive electoral outcomes, others argue that apparently ignorant voters will suffice because they can adapt their behavior to the complexity of electoral choice. To evaluate the validity of these arguments, I develop and analyze a survey of California voters who faced five complicated insurance reform ballot initiatives. I find that access to a particular class of widely available information shortcuts allowed badly informed voters to emulate the behavior of relatively well informed voters. This finding is suggestive of the conditions under which voters who lack encyclopedic information about the content of electoral debates can nevertheless use information shortcuts to vote as though they were well informed.
Fiscal Constraints and Electoral Manipulation in American Social Welfare
Authors: Mebane Walter R.
Published: May 2006

American social welfare policy involves a politically significant fiscal interaction between short-run, pay-as-you-go constraints and long-run equilibrium constraints motivated by the contributory principle and the concept of actuarial soundness. The fiscal constraints induce conflict between benefit recipients and payroll-tax-payers. To support small election-year reductions in payroll taxes, means-tested program benefits are slightly reduced in election years (compared to non-election-year levels under similar economic conditions). The existence of the constraints and of the election-year changes is tested using a multivariate time series regression model of monthly transfer payments and contributions for social insurance during years 1948–87. Short-run dynamics are found to be weakly incrementalist, but otherwise the results support the argument. Extraordinary manipulations are identified during 1972. Special technical features of the econometric analysis are a nonlinear, dynamic specification; robust generalized method of moments estimation; and near cointegration.
More on the European Parliament as a Conditional Agenda Setter: Response to Moser
Authors: Tsebelis George
Published: May 2006

Moser analyzes the cooperation procedure using a model that assumes (1) one dimension and (2) complete information. I show that because of these two restrictive assumptions and his misunderstanding of the strategic implications of Article 189a(1) of the Maastricht Treaty (an article also present in the Single European Act and the Treaty of Rome), Moser's conclusions are mistaken. In particular, his predicted outcomes are incorrect, and his major institutional prediction (that the European Parliament plays no role in decision making except in the second round of the cooperation procedure) is contradicted by thousands of parliamentary amendments, the major part of which are accepted in the first round.
The Long-Run Advantages of Centralization for Collective Action: A Comment on Bendor and Mookherjee
Authors: Schwartz Edward P. , Tomz Michael R.
Published: May 2006

Institutional design can affect the logic of ongoing collective action in groups with heterogeneous members. This article corrects a mathematical error in a seminal article by Bendor and Mookherjee (1987) and shows how the amended result strengthens the case for centralized monitoring and enforcement mechanisms. In solving their original model, Bendor and Mookherjee neglected that groups under centralized control will become increasingly talented over time, as headquarters detects and replaces untalented members. Expected improvements in the talent of the group should heighten the incentive for its members to work and curtail the incidence of costly free riding, as well as reduce the average per-worker cost of production. These gains in efficiency will not materialize in decentralized regimes, where the fraction of talented members will remain constant over time. Depending on the effectiveness of monitoring in the centralized group and the level of patience and talent in society as a whole, centralized regimes can produce greater group welfare than decentralized ones, even when decentralized institutions operate flawlessly.
New Realist Research on Alliances: Refining, Not Refuting, Waltz's Balancing Proposition
Authors: Schweller Randall L.
Published: May 2006

Realism is both a scientific research program and, more traditionally, a political philosophy. All realists share a pessimistic worldview that posits perpetual struggle among groups for security, prestige, and power and that denies the capacity of human reason to create a world of peace and harmony. Recent research by so-called neotraditional realists does not disconfirm Waltz's balancing proposition. Instead, these works have tended to add unit-level variables in order to transform Waltz's theory of international politics into one of foreign policy. The question is not whether states balance or bandwagon—history clearly shows that they do both—but rather under what conditions states choose one strategy or the other.
The Political Foundations of Democracy and the Rule of the Law
Authors: Weingast Barry R.
Published: May 2006

This paper develops a game-theoretic approach to the problem of political officials' respect for political and economic rights of citizens. It models the policing of rights as a coordination problem among citizens, but one with asymmetries difficult to resolve in a decentralized manner. The paper shows that democratic stability depends on a self-enforcing equilibrium: It must be in the interests of political officials to respect democracy's limits on their behavior. The concept of self-enforcing limits on the state illuminates a diverse set of problems and thus serves as a potential basis for integrating the literature. The framework is applied to a range of topics, such as democratic stability, plural societies, and elite pacts. The paper also applies its lessons to the case of the Glorious Revolution in seventeenth-century England.
The Private Production of Public Goods: Organizational Maintenance, Managers' Objectives, and Collective Goals
Authors: Lowry Robert C.
Published: May 2006

I reformulate Mancur Olson's by-product theory of collective action as a theory of resource allocation by interest group managers. I then test alternative hypotheses about managers' objectives drawn from exchange theory and commitment theory. Financial data for 16 environmental citizen groups show that the production of public goods is subsidized by other activities, and revenues from member dues are not affected by spending on public goods. Spending on selective incentives and information generates revenues but also may contribute to the pursuit of collective goals. Estimated marginal revenues from fund-raising and selective incentives show that environmental citizen group managers are not preoccupied with maximizing revenues. Rather, they seek to maximize either spending on public goods or net resources available for influencing public policy and the environment, subject to a budget constraint.
Political Participation in the Chinese Countryside
Authors: Jennings M. Kent
Published: May 2006

The topic of grass-roots participation in China has acquired special interest in light of the local economic and political reforms introduced in the post-Mao period. This paper explores some major modes of participation, issues motivating participation, and the determinants of participation. The findings are based on interviews held in early 1990 with probability samples drawn from four countryside counties. The analysis emphasizes three modes of “autonomous” participation: cooperative actions, voicing opinions to cadres, and contacting representatives. Participants pursued selective and collective goods and were strategic in combining particular modes with particular problem areas. Determinants of participation included traditional resource model predictors but also unique predictors in the form of holding a second occupation, being a party member, and residing in a specific county. Local activists appear to be using new and traditional methods in moving toward more proactive, collective, and strategic forms of behavior.
On the axioms of order and succession
Authors: Bing Kurt
Published: May 2006

Hasenjaeger [2] has answered a question raised by Hilbert and Bernays [4] p. 279, by showing that the axiom

which, within lower predicate calculus, is independent of the remaining axioms of the system (B) p. 273, is no longer independent if the axiom 0 ≡ 0 of (B) is replaced by a ≡ a. The axioms from which (Cov) can be proved form the following system (B1) (obtained from (B), of course, by dropping (Cov) and replacing 0 ≡ 0 by a ≡ a):

In what follows we consider (B1) and also the systems (B′) and (B′1) which are obtained from (B) and (B1) respectively by dropping the induction axiom and which clarify the role of the induction axiom.

1. (B1) is equivalent to (B). For (B) can be obtained from (B1) by Hasenjaeger's result. On the other hand, by pp. 263 and 261, the axioms (<1) and (J1) of (B1) can be proved from the axioms (<3) and

which belong to the system (A) p. 263. Therefore (B1) can be obtained from (A) and the induction axiom, and hence from (B).
Measure-theoretic construction of incomparable hyperdegrees
Authors: Spector Clifford
Published: May 2006

Kleene-Post [10], Spector [14] and Friedberg [3, 4], have given a number of examples of functions which have incomparable degrees of recursive unsolvability satisfying various additional conditions. Our present purpose is to determine to what extent some of these incomparability theorems can be generalized by substituting for “α. is recursive in β” other relations Q(α, β) such as “α is hyperarithmetical in β” (which we shall think of as “α ≦ β”), and to determine what restrictions, if any, need be imposed on Q. As a consequence of our investigation we shall show that there are incomparable hyperdegrees as defined in [9] and [13].
Foundational aspects of theories of measurement
Authors: Scott Dana , Suppes Patrick
Published: May 2006

It is a scientific platitude that there can be neither precise control nor prediction of phenomena without measurement. Disciplines are diverse as cosmology and social psychology provide evidence that it is nearly useless to have an exactly formulated quantitative theory if empirically feasible methods of measurement cannot be developed for a substantial portion of the quantitative concepts of the theory. Given a physical concept like that of mass or a psychological concept like that of habit strength, the point of a theory of measurement is to lay bare the structure of a collection of empirical relations which may be used to measure the characteristic of empirical phenomena corresponding to the concept. Why a collection of relations? From an abstract standpoint a set of empirical data consists of a collection of relations between specified objects. For example, data on the relative weights of a set of physical objects are easily represented by an ordering relation on the set; additional data, and a fortiori an additional relation, are needed to yield a satisfactory quantitative measurement of the masses of the objects.

The major source of difficulty in providing an adequate theory of measurement is to construct relations which have an exact and reasonable numerical interpretation and yet also have a technically practical empirical interpretation. The classical analyses of the measurement of mass, for instance, have the embarrassing consequence that the basic set of objects measured must be infinite. Here the relations postulated have acceptable numerical interpretations, but are utterly unsuitable empirically. Conversely, as we shall see in the last section of this paper, the structure of relations which have a sound empirical meaning often cannot be succinctly characterized so as to guarantee a desired numerical interpretation.