1,004 research outputs found
The quality of group childcare settings used by 3-4 year old children in Sure Start local programme areas and the relationship with child outcomes (Research report DFE-RR068)
"Influenced by research indicating long-term benefits of early childhood programmes for disadvantaged children, the Government of the time set up Sure Start Local Programmes (SSLPs) from 1998 to reduce child poverty and social exclusion. By 2004, 524 SSLPs targeted families with children 0-4 years of age in the 20% most deprived communities. In 2005 it was decided to develop SSLPs further by turning them into children’s centres and roll out the programme nationally, ensuring that comprehensive early education and family support services are available for every community. The National Evaluation of Sure Start has been undertaking research relevant to the development of SSLPs since 2001. This part of the study focuses on 150 SSLP areas from the first four rounds of SSLPs, which are all in deprived areas." - Page iii
Thomas Henry Manning (1911-1998)
Dr. Thomas Henry Manning, Officer of the Order of Canada, former Vice-Chairman and Executive Director of the Arctic Institute of North America, and famed Canadian Arctic expert, died on 8 November 1998 at Smiths Falls, Ontario, after a long illness. He was the author of more than fifty scholarly papers and reports, about half of them on zoological subjects, but he was probably best known for his record as an exceptional Arctic traveller on land and sea. ... Manning was awarded the Bruce Medal of the Scottish Geographical Society and Royal Philosophical Society of Edinburgh in 1944; the Patron's Medal of the Royal Canadian Geographical Society in 1948; and the Massey Medal of the Royal Society of Canada in 1977. He was appointed an Officer in the Order of Canada in 1974 and awarded an honorary doctorate of literature by McMaster University in 1979. Manning was exceptionally tough, vigorous, fearless, patient, hard-working and resourceful, qualities that made him the matchless Arctic traveller and scientist that he was, and earned him respect among Inuit and Southerners alike
Adversarial blockchain queues and trading on a CFMM
We describe a plausible probabilistic model for a blockchain queueing
environment in which rational, profit-maximising schedulers impose adversarial
disciplines on incoming messages containing a payload that encodes a state
transition in a machine. The model can be specialised to apply to chains with
fixed or variable block times, traditional priority queue disciplines with
`honest' schedulers, or adversarial public mempools. We find conditions under
which the model behaves as a bulk-service queue with priority discipline and
derive practical expressions for the relative block and message number of a
transaction.
We study this setup in the context of orders to a CFMM DEX where the
execution price a user receives may be quite sensitive to its positioning in
the chain -- in particular, to a string of transactions scheduled for prior
execution which is not knowable at the time of order creation. We derive
statistical models for the price impact of this order flow both in the presence
and absence of MEV extraction activity.Comment: 20 pages. Keywords: queue, blockchain, mempool, cfmm, mev, dex,
priority discipline, model, sandwich, slippag
A bivariant Yoneda lemma and -categories of correspondences
Everyone knows that if you have a bivariant homology theory satisfying a base
change formula, you get an representation of a category of correspondences. For
theories in which the covariant and contravariant transfer maps are in mutual
adjunction, these data are actually equivalent. In other words, a 2-category of
correspondences is the universal way to attach to a given 1-category a set of
right adjoints that satisfy a base change formula .
Through a bivariant version of the Yoneda paradigm, I give a definition of
correspondences in higher category theory and prove an extension theorem for
bivariant functors. Moreover, conditioned on the existence of a 2-dimensional
Grothendieck construction, I provide a proof of the aforementioned universal
property. The methods, morally speaking, employ the `internal logic' of higher
category theory: they make no explicit use of any particular model.Comment: 60 page
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