Applying methods that others had developed to analyse a similar dataset from North American artifacts, Williams graphed the number of data points for each 200-year period, and made the assumption that for each given area, changes in the number of data points from one period to the next were a good indication of changes in population size — while correcting for the fact that some types of archaeological site can be lost over time owing to processes such as erosion.

Assuming that the population would be between 750,000 and 1.2 million by the eighteenth century, he fit a smooth population curve to the data.

Accurate modelling and prediction of the local to continental-scale hydroclimate response to global warming is essential given the strong impact of hydroclimate on ecosystem functioning, crop yields, water resources, and economic security, in part due to the short length of instrumental measurements available with which to assess climate models.

Here we present a spatial reconstruction of hydroclimate variability over the past twelve centuries across the Northern Hemisphere derived from a network of 196 at least millennium-long proxy records.

CO;2&rft_id=info:pmid/&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.aulast=Jones&rft.aufirst=P.&rft.jtitle=J. Clim.&rft.volume=10&rft.spage=2548&rft.epage=2568&rft.date=1997&rft.atitle=Estimating sampling errors in large-scale temperature averages&rfr_id=info:sid/nature.com: Nature.com&id=doi:10.1175/1520-0442(1997)0102.0.

Even at its best it is limited in its coverage of different facets of history.

Thus one does not even begin to understand the development and growth of human society in Ceylon in its totality.

Annual Report, 19); today, some forty years later, this statement still applies.

Several factors have been detrimental to the growth of this aspect of archaeological research.