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What Is Sociolinguistics?, G. Van Herk (2012), Wiley-Blackwell, ISBN 978-1-405-19318-4

Core Outcome Set-STAndards for Development: The COS-STAD recommendations

BACKGROUND The use of core outcome sets (COS) ensures that researchers measure and report those outcomes that are most likely to be relevant to users of their research. Several hundred COS projects have been systematically identified to date, but there has been no formal quality assessment of these studies. The Core Outcome Set-STAndards for Development (COS-STAD) project aimed to identify mini...

There Is a Van Douwen Mad Family

It is easily seen that Van Douwen MAD families exist under CH, and more generally under MA. The question of whether they always exist was raised by E. van Douwen and A. Miller. It occurs as problem 4.2 in A. Miller’s problem list [7]. Zhang [8] discusses this problem and proves that Van Douwen MAD families of various sizes exist in certain forcing extensions. In this section we will prove in ZF...

Being Van Kampen is a universal property

Colimits that satisfy the Van Kampen condition have interesting exactness properties. We show that the elementary presentation of the Van Kampen condition is actually a characterisation of a universal property in the associated bicategory of spans. The main theorem states that Van Kampen cocones are precisely those diagrams in a category that induce bicolimit diagrams in its associated bicatego...

On the van der Waerden numbers w(2;3,t)

On the van der Waerden numbers w(2; 3, t) Abstract In this paper we present results and conjectures on the van der Waerden numbers w(2; 3, t). We have computed the exact value of the previously unknown van der Waerden number w(2; 3, 19) = 349, and we provide new lower bounds for t = 30, we conjecture these bounds to be exact. The lower bounds for w(2; 3, t) with t = 24,. .. , 30 refute the conj...