Let $A$ be a Banach algebra and $E$ be a Banach $A$-bimodule then $S = A oplus E$, the $l^1$-direct sum of $A$ and $E$ becomes a module extension Banach algebra when equipped with the algebras product $(a,x).(a^prime,x^prime)= (aa^prime, a.x^prime+ x.a^prime)$. In this paper, we investigate $triangle$-amenability for these Banach algebras and we show that for discrete inverse semigroup $S$ with...

This paper addresses an estimation problem of an additive functional of φ, which is defined as θ(P ;φ) = ∑ k i=1 φ(pi), given n i.i.d. random samples drawn from a discrete distribution P = (p1, ..., pk) with alphabet size k. We have revealed in the previous paper [1] that the minimax optimal rate of this problem is characterized by the divergence speed of the fourth derivative of φ in a range o...

A fundamental quantity in statistical decision theory is the notion of the minimax risk as5 sociated with an estimation problem. It is based on a saddlepoint problem, in which nature plays the 6 role of adversary in choosing the underlying problem instance, and the statistician seeks an estimator 7 with good properties uniformly over a class of problem instances. We argue that in many modern 8 ...

We investigate minimax Latin hypercube designs in two dimensions for several distance measures. For the `-distance we are able to construct minimax Latin hypercube designs of n points, and to determine the minimal covering radius, for all n. For the `1-distance we have a lower bound for the covering radius, and a construction of minimax Latin hypercube designs for (infinitely) many values of n....

Minimax parameter estimation aims at characterizing the set of all values of the parameter vector that minimize the largest absolute deviation between the experimental data and the corresponding model outputs. It is well known, however, to be extremely sensitive to outliers in the data resulting, e.g., of sensor failures. In this paper, a new method is proposed to robustify minimax estimation b...