We consider a descriptive version of Kakutani equivalence for Borel automorphisms of Polish spaces. Answering a question of Nadkarni, we show that up to this notion, there are exactly two Borel automorphisms: those which are smooth, and those which are not. Using this, we classify all Borel R-flows up to C∞ time-change isomorphism. We then extend the notion of Kakutani equivalence to all (not n...

Vapnik and Cervonenkis, and Talagrand, have characterized the Glivenko-Cantelli property for independent random variables. We show that these characterizations fail to hold for general stationary ergodic processes. Appears in Statistics and Probability Letters, 24 165-168, 1995. ∗Andrew Nobel is a Beckman Institute Fellow at the University of Illinois Urbana-Champaign. Correspondence to: Andrew...

An equigenerated monomial ideal [Formula: see text] in the polynomial ring is a Freiman if text], where analytic spread of and least number generators text]. In this paper, we classify certain classes Borel-type ideals, including Borel ideals with multiple principal text]-Borel which are Freiman.

Title of dissertation: THE BOREL COMPLEXITY OF ISOMORPHISM FOR SOME FIRST-ORDER THEORIES Richard Rast, Doctor of Philosophy, 2016 Dissertation directed by: Professor Michael C. Laskowski Department of Mathematics In this work we consider several instances of the following problem: “how complicated can the isomorphism relation for countable models be?” Using the Borel reducibility framework from...

See [Oli04]. In [AdKech00], Adams and Kechris showed that the relation of equality on Borel sets (and therefore, any Borel equivalence relation whatsoever) is Borel reducible to the equivalence relation of Borel bireducibility. (In somewhat finer terms, they showed that the partial order of inclusion on Borel sets is Borel reducible to the quasi-order of Borel reducibility.) Their technique was...

We prove a classification theorem of the “Glimm–Effros” type for Borel order relations: a Borel partial order on the reals either is Borel linearizable or includes a copy of a certain Borel partial order ≤0 which is not Borel linearizable. Notation. A binary relation 4 on a set X is a partial quasi-order , or p.q.-o. in brief, on X, iff x 4 y∧y 4 z ⇒ x 4 z, and x 4 x for any x ∈ X. In this case...

We show that Hausdorff measures of different dimensions are not Borel isomorphic; that is, the measure spaces (R, B, H) and (R, B, H) are not isomorphic if s 6= t, s, t ∈ [0, 1], where B is the σ-algebra of Borel subsets of R and H is the d-dimensional Hausdorff measure. This answers a question of B. Weiss and D. Preiss. To prove our result, we apply a random construction and show that for ever...

In this paper we give some characterizations of topological extreme amenability. Also we answer a question raised by Ling [5]. In particular we prove that if T is a Borel subset of a locally compact semigroup S such that M(S)* has a multiplicative topological left invariant mean then T is topological left lumpy if and only if there is a multiplicative topological left invariant mean M on M(S)* ...

In this paper, we construct a counter-example to a question by Cantelli, asking whether there exists a non-constant positive measurable function φ such that for i.i.d. r.v. X,Y of law N (0, 1), the r.v. X + φ(X) · Y is also Gaussian. For the construction that we propose, we introduce a new tool, the Brownian mass transport: the mass is transported by Brownian particles that are stopped in a spe...

We consider the estimation of error distributions in least squares identiication of distributed parameter systems. Asymptotic properties of approximate error sequences are developed. In particular, we examine consistency and asymptotic normality of empirical estimates of the error distribution. The consistency obtained is analogous to the Glivenko-Cantelli theorem. For asymptotic normality, we ...