Determining nugget: sill ratios of standardized variograms from aerial photographs to krige sparse soil data

Maps of kriged soil properties for precision agriculture are often based on a variogram estimated from too few data because the costs of sampling and analysis are often prohibitive. If the variogram has been computed by the usual method of moments, it is likely to be unstable when there are fewer than 100 data. The scale of variation in soil properties should be investigated prior to sampling by computing a variogram from ancillary data, such as an aerial photograph of the bare soil. If the sampling interval suggested by this is large in relation to the size of the field there will be too few data to estimate a reliable variogram for kriging. Standardized variograms from aerial photographs can be used with standardized soil data that are sparse, provided the data are spatially structured and the nugget:sill ratio is similar to that of a reliable variogram of the property. The problem remains of how to set this ratio in the absence of an accurate variogram. Several methods of estimating the nugget:sill ratio for selected soil properties are proposed and evaluated. Standardized variograms with nugget:sill ratios set by these methods are more similar to those computed from intensive soil data than are variograms computed from sparse soil data. The results of cross-validation and mapping show that the standardized variograms provide more accurate estimates, and preserve the main patterns of variation better than those computed from sparse data.

'A theatre of ruins'. Edward Bond & Samuel Beckett: theatrical antagonists

The playwright Edward Bond has long made known his antagonism to dramatists allied to Martin Esslin’s Theatre of the Absurd. The work of Samuel Beckett has come in for particular criticism by Bond. Using published writings (and unpublished correspondence between myself and Bond), I hope to trace the development of this antagonism between ‘Bondian’ and ‘Beckettian’ views of theatre. However, this article will also set out to argue that both early work such as The Pope’s Wedding (1962), and more recent work such as Coffee (1995), make use of motifs, characters and ideas from Beckett’s theatre. The article will set out provisional reasons why Bond, despite his misgivings, is not averse to incorporating elements from Beckett’s ‘theatre of ruins’, as he terms it, into his own work.

Edward Bond & the celebrity of exile

A shibboleth has grown up around the work of Edward Bond. The tag ‘controversial dramatist’ has continued to dog both the man and his work. This article will hope to explore some of the contradictory, and sometimes frustrating manifestations that such ‘celebrity’ has produced. Since the reception of The War Plays [1985] by the Royal Shakespeare Company at the National Theatre Bond has largely withdrawn his work from mainstream British theatre. Since the late 1990s he has looked to a new home – La Colline Theatre – in France, to premiere new work and run retrospective seasons of older plays. Here, Bond's celebrity is of a different kind, and has allowed him to enhance and develop his work as a playwright, director and writer about theatre. While this article draws on secondary sources it also uses material based on personal correspondence with Edward Bond.