Tree initialisation techniques for genetic programming (GP) are examined in [4,3], highlighting a bias in the standard implementation of the initialisation method Ramped Half-n-Half (RHH) [1]. GP trees typically evolve to random shapes, even when populations were initially full or minimal trees [2]. In canonical GP, unbalanced and sparse trees increase the probability that bigger subtrees are s...

We explore the connections between the well-studied Aztec Diamond graphs and a new family of graphs called the Half-Hexagons, discovered by Jonathan Novak. In particular, both families of graphs have very simple domino shuffling algorithms, which turn out to be intimately related. This connection allows us to prove an “arctic parabola” theorem for the Half-Hexagons as a corollary of the Arctic ...

We consider the minimum number of zeroes in a 2m 2n (0; 1)-matrix M that contains no m n submatrix of ones. We show that this number, denoted by f(m; n), is at least 2n + m + 1 for m n. We determine exactly when this bound is sharp and determine the extremal matrices in these cases. For any m, the bound is sharp for n = m and for all but nitely many n > m. A general upper bound due to Gentry, f...

Consider the minimum number f(m,n) of zeroes in a 2m×2n (0, 1)-matrixM that contains no m×n submatrix of ones. This special case of the well-known Zarankiewicz problem was studied by Griggs and Ouyang, who showed, for m ≤ n, that 2n+m+1 ≤ f(m,n) ≤ 2n + 2m − gcd(m,n) + 1. The lower bound is sharp when m is fixed for all large n. They proposed determining limm→∞{f(m,m+ 1)/m}. In this paper, we sh...

Timo Henckel is a Fellow in international and development economics at the Crawford School of Economics and Government, The Australian National University Vanuatu’s economy paints a picture of contradictions: it has continued on the recent growth path with low inflation, government budget surpluses, and increased capital inflows. Yet successful management of the economy has not translated into ...

followed by premature RB beats, we must assume that RB complexes do not express conducted sinus impulses but are, in fact, escape beats, also suggested by their short H-V interval. The diagram of Figure 1 reflects a 2:1 form of A-V nodal block. This phenomenon, however, would have been the same with any other form of second-degree A-V block provided that two levels of block occur, and no retrog...

Narration will be mainly focused on the origin, course and aftermath of four far-reaching initiatives that bloomed in Italy at almost the same time, in a few months encompassing 1954 and 1955; a choice which implies unfair omission of other worthwhile but less influential happenings.

This article examines several major political and cultural issues with which the citizens of Azerbaijan are currently grappling. It considers the role of the Nogorno-Karabakh conflict and its aftermath, irredentist claims made by some on Azerbaijani portions of Iran, the place of women in society, and the role of oil. Present in all these topics, however, is the common theme of how Turkish, Rus...

Hemi-spatial neglect is a disabling, neuropsychological impairment that restricts the ability to attend to incoming information on one side space. Most frequently associated with a lesion to the right hemisphere, the disorder is strongly predictive of general functional recovery from stroke. Although the standard therapy is of limited effectiveness, pilot studies indicate that more effective tr...