GIS graphics vs. spatial statistics: how do they fit together?Kenneth L. Kvamme . . .

A New Heritage Bulletin Bo~u'dKeith Dewar. . . . . . . .

VB·GIS 3D - A Development Report on a GIS Model for ArchaeologyCarlos Reynoso

A GIS Salesman and the Devil : .

Economical possibilities for the rectification of digital imagesJohn G. B. Haigh and Stanley S. Ipson .

.DBF programs for faunal analysisDavid L. Carlson . . . .

A review of the MCN Standards Framework for Computer Interchange of Museum In-formationJonathan Moffett .

Using Authorware Pro 2.0 for teaching material within British Universities - Evalu-ationAnja Wolle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 17

Direct Object Computer Scanning (DOCS)William H. Waldren. . . 21

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./eremy Huggett BA, PhD, MII'l\, (Department of Archaeology, Glasgow University)Gary Lock BA, PhD, MlI'l\, (institllle of Archaeology, University of Oxford)Paul Reilly BA, PhD, MlI'l\, (IBM UK Scientific Centre)Dick Spicer BA, PhD, (School of Computing, Staffordshire University)Kenneth L. Kvamme PhD, (University of Boston)Zoran Stancic PhD, (Univer.l"ity of Ljubljana)

Archaeological Computing NewsletterThe Institute of Archaeology36, Beaumont StreetOXFORD OXI 2PGUnited Kingdom

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Ranter's cornerGIS graphics vs. spatial statistics: how do they fit together?

One impression I frequently come away with after viewing people working with a GeographicInformation System (GIS) is how often they seem to discover patterns or relationships in theirdata. Merely by displaying maps of, say, archaeological sites overlaid on other spatial vari-ables, some sort of new association or tendency is typically realized or confirmed. Computervisualization tools, particularly in GIS contexts, are encouraging archaeologists to work in-ductively, to become more intimately acquainted with their data. In this way they are causingsomewhat of a revolution in the way archaeologists conduct their research.

In the heyday of the 'New Archaeology' it was pretty much required to work in a 'deductive'fashion, with a priori specified models or theories which were then tested with data. Now,with the computer graphics revolution and GIS, research often begins with the discovery ofpatterns in our data at the computer terminal, which leads us on to formulate new questionsand discover new relationships in a highly interactive process between graphic data portray-als and what might be termed 'running hypotheses.' The outcome is that we now often buildmodels from the ground up, using a 'data-upward' strategy (in contrast with research in the'theory-downward' norm of the previous decades). Both approaches, and their interaction, arenecessary for a healthy and fruitful research posture in any discipline. Although the forerun-ners of data exploration clearly lie in more traditional statistical techniques, these approachesnever have been user-friendly (requiring considerable training), in contrast to modem com-puter software. We can thank computer graphics for finally opening the doors of exploratoryspatial analysis.

Yet, although no one will dispute that data visualization is an essential research tool (indeed,it forms the basis of the EDA school of statistics), the picture is not all rosy. The ease withwhich GIS graphics can be generated has transformed the nature of what constitutes regionalresearch. Only a few years ago a formal statistical analysis typically was required to formand present conclusions. Now the goal of research often is simply the production of a well-designed, computer-generated graphic. Indeed, GIS-produced images are sometimes presen-ted as 'spatial analyses.' Are they? Should they be presented as such?

We must realize that the human eye is easily fooled-it might perceive patterns in an imagewhich really do not exist or fail to recognize trends that do. Moreover, it is easy to construct agraphic that emphasizes certain patterns and downplays others, for example, especially whenwe have at our disposal advanced design tools for two-, three-, or four-dimensional viewsand phosphorescent colors numbering in the millions. There already are too many GIS-basedstudies where one must question whether there is any substance behind the stunning visualproducts.

While appreciating the power of visualization as a foundation of spatial research we must, atthe same time, reassert the importance of formal statistical methods. The argument for a dualapproach to spatial investigations, one that incorporates visualization with quantitative ana-lysis, has been made several times in recent years and is germane at this point. Visualizationtools are essential because simple statistics cannot convey the essence of spatial pattern in thesame way that an effective graphic can. On the other hand, statistical methods can informus of the existence of tendencies or relationships which are difficult, or even impossible, tovisualize.

Additionally, objective quantitative measures of the strength of patterns or relationships areoften desirable, for example, as a basis for comparisons with other results and samples. At

the very least, statistical tests should playa confirmatory role in documenting the existence of'visually apparent' tendencies. Both approaches to regional spatial investigations are neces-sary and should routinely be employed.

This task will not be easy, however. Most contemporary GISs typically offer limited function-ality in the way of quantitative spatial analysis, so even with good intentions it is difficult toundertake. One must usually extJ"actthe data from the GIS and input it to a statistical softwarepackage for analysis. This is part of the challenge of contemporary computer archaeology!

Kenneth L. KvammeDepartment of ArchaeologyBoston University675, Commonwealth AvenueBoston MA 02215USA

VB·GIS 3D - A Development Report on a GIS Model forArchaeology

VB·GIS 3D is an experimental computer system for exploration, analysis, hypothesis testingand statistics in spatial or distributional archaeology. It is a working platform programmedin Microsoft Visual Basic for Windows, strictly based on an artificial intelligcnce prototypedesigned in PDC Prolog a couple of years ago. It also works on Windows NT* environments.The goal of the design is to provide a single open system with a state of the art graphic inter-face. The program is aimed to interact with any other existing application, local or remote.It was globally designed and programmed by Professor Carlos Reynoso; some routines weredevised by Damian Castro, graduate student of Anthropology at the Universidad de BuenosAires. Founds were granted by a CONICET program of research and development (PID 40 1/89).

Heritage Interpretation International in cooperation with Massey University in New Zealandhave developed a BB for all interpreters, heritage managers, academics and students interestedin the interpretation and presentation of the worlds heritage.

Purpose: the purpose is to allow the free exchange of information and ideas on interpretationand the management of heritage sites world wide. It is hoped that it will also allow for theopen discussion of issues of interest to heritage professionals, academics and students.

Send the following message to li stserv~assey . ac. nz containing the following:

SUBSCRIBE HERITAGE your name

For example; SUBSCRIBE HERITAGE Keith Dewar

More information from the author.

Keith DewarManagement SystemsMassey UniversityPrivate Bay 102904North Shore MSCAuckland, N.Z.email: K.Dewar@massey.ac.nz

VB·GIS has a very rich and customizable interface with menus, graphic toolbars, commandbuttons and dialog boxes. The operation of the program has a complete help system associ-ated with every command or option available at any point. All the menu items have keyboardacceleration traps which make it possible to keep control of the interface by keyboard (insteadof mouse) or by means of voice pilot macros using Windows Sound System or any other sim-ilar sound kit. This means that complex sequences of commands can be controlled both byvoice or by normal Windows macro procedures. The mouse is the natural choice, however.For an easier and more controlled operation, the interface is highly adaptive: only the logic-ally correct sequences of operation are available at a given instance. If the user needs someadditional copy of a complex form, such as a graphic or an spreadsheet, he can create it at will.Several graphics and tabulated data can be then compared, modified and inter-operated.

The design has carefully avoided the dead-ends and incongruous menu arrangements so com-mon in standard archaeological software. Here even the most complex procedures are bothopen and self- contained: if some operation is selectable, then it can be done right down us-ing the available data. VB·GIS also includes a systematic set of interpretive aids to deal withstatistic procedures and results, and even some basic statistic tables (such as chi square) are athand for comparisons. Another primary design goal was to turn the most complex statisticsunderstandable even for the non-specialist.

The program was also developed to be complementary to other software alternatives, no mat-ter how much functionally gets overlapped. The system is compatible with almost any dataformat: dBase, Excel, Lotus, Quattro, Paradox, Btrieve, FoxPro, Oracle, SQL Server (throughODBC), Surfer, Arcospace, text files. The ODBC driver involves that any database server maybe used without recompiling the system. The data can be brought to the internal matrices inseveral ways, from clipboard copy-and-paste to direct import.

Perhaps one of the program's most valuable features is the open endedness of the interactionwith the user, who can choose between a lot of options regarding data input and representationstyle. For example, the program can be used to generate automatically artifact sets from poin-ted analogical coordinates. Individual data items can be dragged and dropped on the squaregrid or generated by more or less constrained random algorithms. The data can be edited dir-ectly on one of the various spreadsheets provided, or imported from data files, or passed throgh

Over the spreadsheets, the edition tools are likewise sophisticated: the user can drag and drop,make multiple selections, hide and display rows and columns, import and export any kind ofdata, pass a range to another program through the clipboard and plot several kinds of statislicalgraphics with simple commands from the menus, the keyboard or the mouse. Every cell of lhcspreadsheet is individually configurable in terms of font, color, pattern, border and size. Theuser may import data in any format, with any number of fields, and adjusllhe records lO LIlt;

system's expected scheme later, using the available editing facilities.

Concerning graphics, VB·GIS has a full featured bitmap toolbox which allows for internalmapping design. A special graphic library includes icons, vectors and bitmaps for markingobjects related to sites, non-sites, planls and grids, such as scale rules, cardinal pointers andarchaeological signals. The system accepts scanned pictures in PCX, BMP, RLE, GIF, TIF,TGA, JPEG and WMF formats. 3D images in AutoCAD DXF format can be imported andactivated for further rotations and transforms. Some other vector and raster formats will beadded in the next release. The graphic interface provides separate graphic tools for markingregions, with separate zooming, rotation and stretching. It is possible to work on several mapsat the same time, to select and crop a region from a greater chart or to tile partial maps in acomposed image.

Graphic processing capabilities are virtually unlimited, including facilities and features suchas transparent maps and data, addition, abstraction or substraction of image elements, imageedition on charge of other specialized programs, combination of over 13 different drawingmodes and 8 fill styles, analytical mapping from conceptual data, layer integration and se-gregation, perspective mapping and so on.

An important section of the program is itself a photographic laboratory utility with severaloptions for controlling bright and color contrast, border smoothing and sharpening, blurring,masking, posterizing and filtering of maps and aerial snapshots. Color depth is selectable atany moment from I to 24 bits, specifying dithering and palette options. This section is technic-ally as elaborated as any photo edition program available in the market, and certainly it's alsofaster, even when working with more than 16 million colors. From this particular screen anybitmap format can be converted to any other, including the highly compressed JFIF standard.

VB·GIS features second generation Object Linking and Embedding technology, both as OLE2 object edition and OLE Automation. This means that data types regarding maps and data-base may include video clips, sound files, rasterized photos, vector data, spreadsheets, wordprocessor documents, statistic graphs and whatever can be managed by the installed platform.The internal photo lab uses a powerful Visual Basic library, Image KnifeNBX, made by Me-dia Architects of Portland, Oregon.

VB·GIS also allows for automatic generation of papers and reports, with publication qualityoutput of text, tables and graphics. Documents like this one with additional pictures inserted,for instance, may edited using a standard word processor and passing all the graphic items online from VB·GIS, without intermediate files. Several special PostScript facilities for printingand plotting have been designed specifically for VB·GIS, including grayscales and texturessupport. The program should use any output device installed for Windows without specificsetup; all the capability of the Windows drivers regarding fonts, page sizes, orientation, res-olution, dithering, etc, are automatically available.

VB·GIS is able to deal both with intrasite and intersite data. This version in particular is moreeffective in intrasite analysis, but a lot of intersite capabilities is in the pipeline. The archae-ologist is free to choose between quadrats, regions, transects or exact coordinates, workingwith a maximum of 32767 elements, types or layers (depending of the context). l1le goal ofthis aspect of VB·GIS design was to set all the common archaeological approaches ever men-tioned in the bibliography, together with their documentation, critics and shortcomings, in anenvironment suitable for cross-matching.

Following are listed some of the 2D statistic facilities already implemented.

I Basic Calculations: Distance, Angle and Area2 Simple Global Density3 Density by Artifact Type4 Johnson's Local Density Analysis5 Spatial Scale6 Poisson Distribution and Chi Square7 Whallon's Polythetic Association8 Unconstrained Clustering9 Hodder and Okell's A Coefficient

10 Luton and Brown's Contiguity AnalysisII Point -to-item Distance (Pielou)12 Contingency tables (Bray, Driver and V Coefficients)13 Nearest neighbor of Order N14 Nearest Neighbor Analysis15 Linear Nearest Neighbor16 Morisita Index17 Cluster Analysis: Cutoff Radio Maps18 Cluster Analysis: Kintigh and Ammerman's Heuristics19 Dimensional Analysis of Variance20 Kriging21 Sampling22 Regression Analysis23 MRPP24 Simulation: Random Walk25 Simulation: Gravity Model26 Contouring and Trend Surfaces

The search for new procedures and algorithms for their inclusion in VB·GIS is yet open. Ahost of standard simple statistics (mean, average, maximum, minimum, standard deviation,best fit, etc) are always accessible from the graphic and spreadsheet windows. More than 50additional statistic routines are planned to be implemented in Release 1.0 before December,1994. By the way, any statistical operation can be applied step by step using formulas in thespreadsheets.

VB·GIS has an MDI form specific for data edition and analysis. In fact, this Multiple Doc-ument Interface provides two fully configurable spreadsheets and two statistic graphs to ploton. Graphs and spreads can be copied at will, even when empty; so, the real scope of the in-terface is undefined, bounded only by the available memory and resources. The spreadsheets,featuring the extraordinary SpreadlVBX by Far Point totally embedded, hold up to 2 billioncolumns and the same number of rows each: a lot more than any known conventional spread-sheet on earth, including the forthcoming version of Excel.

Statistic procedures in VB·GIS yield three kind of output data: very detailed mathematicalresults (blocked in a 'message' window), tabulated data over one or more spreadsheets, andstatistical graphs. The graphs are in fact a set of advanced analytical tools capable of plotting3800 points of data, much more than could be intelligible on a single image. VB·GIS has IIdifferent types of graph (plain pies, 3D pies, bars, 3D bars, Gantt, line, log/lin, area, scatter,polar, HLC), and each type has several individual styles. Every aspect of the graph's layoutis customizable: titles, legends, labels, ticks, scales, grids, background or foreground colors,fill patterns, global size, fonts and so on. Any graph is printable in a single step, involving allthe necessary adaptation to the hardware capabilities.

There is no limit to the number or sizes of data bases associated to an archaeological set. Oncedefined a data base, its content is ready to be selectively mapped by means of SQL (StructuredQuery Language) filtering criteria. These criteria, in turn, may be quantitative (e.g. artifactsweighter than 8 pounds), qualitative (e.g. objects colored red) or mixed. Data have not to bere-entered: any already existing database can be joined as a VB·GIS information collection,provided that accurate coordinate data are annexed later.

VB·GIS includes the magnificent 3D Graphic Tools developed by Mark Owen for Micro Sys-tem Options, Washington, USA. It is one of the few libraries for complex 3D drawing availablefor Windows.

An operating release of VB· GIS will be ready by August 1994. It will be not expensive (about$150). Future revisions of VB·GIS will include features and capabilities today in develop-ment. Some of them are worth mentioning in this context: new special mapping controls de-signed by GeoSoft Limited (Leeds, U.K.), improved 3D graphic tools from Mark Owen, 32bit computing for extremely huge arrays, a Rushmore algorithm for databases, Thiessen poly-gons, Delaunay triangles, more powerful bitrnap edition tools and embedded scanner manage-ment.

Thanks to this library and to the programming approach, VB·GIS has an open field of pos-sibilities dealing with three-dimensional items: you may act upon 3D maps projected from ascanned 2D surface, you may use 3D projections to stress statistical results such as contouringcurves and trend surfaces, and you may plot 3D archaeological scatters in a 3D space. Andyou can do it all together, if you like and your machine has the resources. VB·GIS is ableto keep control of four different three-dimensional surfaces at a time; hundreds of overlap-ping surfaces may be plotted when running on Windows NT. A surface can denote anything:a roof, a topographical terrain, a water level or, again, all of these things together. Any math-ematical function which renders a 3D surface can be plotted in one phase. A set of 3D basicfigures (spheres, cylinders, cones, cubes torroids) is also at hand. The graphical plotting of3D objects supports up to 16 million colors with 32 bit boards.

Given a three-dimensional object, VB·GIS uses the 'camera and lens metaphor' to situate theviewpoint. There are separated controls for object orientation, scale and placement, with op-tions between parallel and perspective projection. Hidden surface removal is automatic (it'spossible to turn it off, however), and even the transparency index is subject to change workingboth with wireframes or compact surfaces.

One of the program's most evolved aptitudes concerns lighting: the light can be of any colorand intensity, and the (different) light sources can be placed anywhere. A special setting al-lows to simulate light hazing, to turn darker the most distant objects or to reproduce specificlight conditions, an underwater scenario or a sunset, for instance. Shading (flat or Phong) isalso selectable. Light, surface color, shades and refraction values interact with texture settings,such as rock, wood and bumps to give realistic landscapes.

VB·GIS has a repertory of interpolation methods: Bspline, Hermite, Catmullrom, Bezier andBeta surfaces are selectable, with further partitioning and subdivision. Additional texturesmay be used to identify a bitmapped image file which will be projected onto the facets of agiven object.

Some archaeologists have already suggested interfaces and procedures: Ian Johnson, of theUniversity of Sydney, gave us substantial bibliographical support for a better implementationof the local density analysis; Foss Leach, of the University of Auckland, New Zealand, askedfor a specific 3D interface in terms of Euler angles. We have to talk a lot with Sebastian Rahtzof Southampton, who is programming his WinDig also in Visual Basic. Indeed, VB·GIS wantsto be an open system without a definite ending. So, any suitable idea should be truly appreci-ated.

Prof. Carlos ReynosoUBA-CONICETreynoso©pccp.com.arbillyr©microsoft.com

(Eds - This is an important comment offered by our Central and Eastern European Editor,Dr Zoran Stancic, based on his considerable experience of working with GIS).

There was once a super GIS salesman who travelled the world with a great 'can do anything'GIS demo. One day while dashing through O'Hare Airport to catch his next flight he died ofa heart attack.

At the pearly gates he was judged to have led a borderline life and so was given the choiceof heaven or hell. He could look into the doors of each and as the door to heaven opened heheard wonderful harp music and saw people floating serenely on clouds. A quick peek throughthe doors to down-under revealed total debauchery with loud rock and roll music, dancingdrinking and some serious partying.

As he met with his maker again, he decided that Heaven was very nice but he really did feelthat the other place was more his style. 'Think carefully', he was advised but no, that was hiswish.

Last but not least, VB·GIS has a complete database and information system embedded, dis-tinct from the tabular data itself. This system is operated both in relation to artifacts or tocoordinate points, and the information corresponding to each item may be of any type: pho-tos, presentations, descriptive data, documents, matrices, video, sound or movie clips, vectors,compound objects and even applications with specifically loaded data. Internally, all complexdata is represented as a reference to an object which could link to other objects.

As the doors opened again and he was pushed through, the intense heat hit him together withoverpowering moans of sorrow and anguish. As he grovelled before the Devil, he pleaded'where is the party?'. The Devil sneered and replied 'that was the demo, welcome to the realthing!'.