Graphics excellence

As an integral component of Microsoft Office, the spreadsheet program Excel is installed on many personal computers. Thus, a widespread basic expertise can be assumed. Although initially designed for business calculations and graphics, Excel is also extremely useful for scientific purposes. Its matrix capabilities, as well as the optimisation add-in solver, are not widely known but can often be applied in order to quickly resolve quite complex multivariate problems. We have used Excel 2002 but any other version will do equally well. 

The new formalism is especially useful for parallel and distributed computers, since the communication intensity is exceptionally low and excellent load balancing is easy to achieve. In fact, we have used cluster of workstations (Silicon Graphics) and parallel computers - Terra 2000 and IBM SP/2 - to study dynamics of proteins. 

Mortimer, R. G., 1999. Mathematics for Physical Chemistry, 2nd ed. Academic Press, San Diego, CA. [This book contains an introduction to computer use with brief comments, references and sources to BASIC, Excel, graphics, curve fitting, and Mathematica.]... 

Data on chemical properties such as self-dissociation constants for sulfuric and dideuterosulfuric acid (60,65,70,71), as well as an excellent graphical representation of physical property data of 100% H2SO4 (72), are available in the Hterature. Critical temperatures of sulfuric acid solutions are presented in Figure 10 (73). 

Years ago plastic scale models were fabricated for each plant under construction, providing excellent three-dimensional representations of the actual facilities. Today, in the age of the microcomputer, it is quicker, easier, and much cheaper to generate models by means of computer graphics. 

Copy under the Edit menu is used for eopying graphics and data onto the clipboard. This can later be imported into such programs as Microsoft Word and Excel. There are two modes of operation ... 

The Atari ST was chosen because it has a high performance graphics engine, an advanced operating system, and a large amount of easily accessible memory. These features make it an excellent value for the money. The IBM PC may be the computer of choice for business packages, but it has less technical and cost justification when used to run custom software. 

In a tiny fraction of cases, a quick formula can be used. For most cases, the analysis uses an options tree, with one leaf per possible outcome. However, this falls prey to the curse of dimensionality —the number of leaves on the tree grows exponentially in the number of risk and decision dimensions considered. Thus only a limited, simple set of situations can be optimized in this way because one has to severely limit the decisions and risks that are considered. Tools available to help automate and simplify options analysis, widely used in pharmaceutical project evaluation, include Excel addons such as R1SK [11] and more graphically based solutions such as DPL [12]. Both of these support the creation and evaluation of decision trees and of influence diagrams Figure 11.2 shows a simple example of each of these. A primer in applied decision theory is Clemen s book Making Hard Decisions, other sources may be found in the website of James Vornov, Director of Clinical Research at Guildford Pharmaceuticals, a recent convert to decision theory for options analysis [13]. 

Most of the algorithms and formulae discussed in this chapter can be implemented as expressions in computer spreadsheets, and the rest as simple computer programs. Most are also incorporated into the Microsoft Excel spreadsheet program by the Isoplot add-in (Ludwig 1999, in press) as user-available functions and graphical routines (Appendix III). 

We may compare our graphical result with the result obtained from solving for X and y by nonhnear regression fitting of the experimental rate curves to the power law form of eq. (8). Carrying this out using the Excel Solver tool... 

The interactive SAS Import Wizard provides an easy way to import the contents of Microsoft Excel and Access files into SAS. Here again, the Import Wizard is essentially a graphical user interface that builds the PROC IMPORT code for you. Begin in the interactive SAS windowing environment by selecting File from the toolbar and then Import Data... from the drop-down menu. A window like the following will appear, where you can select Microsoft Excel as a standard data source. 

Note that for box and survival plots, PROC GPLOT is listed as an alternative. Although PROC BOXPLOT and PROC LIFETEST produce excellent graphs by themselves, sometimes it is necessary to make modifications to the output in a way that these procedures cannot handle directly. When modifications are needed, PROC GPLOT is an excellent choice. Also note that PROC REG and PROC UNIVARIATE are listed as options for scatter plots and box plots, respectively, as they can be useful in producing lower-resolution graphics for statistical appendices. 

The microcomputer should incorporate a VDU and have high-density colour graphics capability (up to 1760(x) x 1280(y)). This enables IR-spectra to be displayed on the screen of the VDU with excellent definition so that comparisons, the results of scale expansions and other spectral manipulations can immediately be seen. Parameters such as range, scan time, data point interval, etc., are set and monitored under microprocessor control and stored along with the spectrum. During the scanning of a sample, several thousand data points may be collected and stored in RAM which should be able to accommodate and display at least three spectra simultaneously. There is a wide range of manipulations that can be performed by the analyst on stored spectra, e.g. 

In addition to the Premium Excel Solver and Optquest, there are many other software systems for constrained global optimization see Pinter (1996b), Horst and Pardalos (1995), and Pinter (1999) for further information. Perhaps the most widely used of these is LGO (Pinter, 1999), (Pinter, 2000), which is intended for smooth problems with continuous variables. It is available as an interactive development environment with a graphical user interface under Microsoft Windows, or as a callable library, which can be invoked from an application written by the user in... 

The Kaplan-Meier estimates produce a step function for each group and are plotted over the lifetime of the animals. Planned, accidentally killed, and lost animals are censored. Moribund deaths are considered to be treatment related. A graphical representation of Kaplan-Meier estimates provide excellent interpretation of survival adjusted data except in the cases where the curves cross between two or more groups. When the curves cross and change direction, no meaningful interpretation of the data can be made by any statistical method because proportional odds characteristic is totally lost over time. This would be a rare case where treatment initially produces more tumor or death and then, due to repair or other mechanisms, becomes beneficial. 

There are a number of excellent references available for those who would like to pursue statistical graphics more. Anscombe (1973) presents an excellent short overview, while others (Tufte, 1983, 1990, 1997 Schmid, 1983 and Young, 1985) provide a wealth of information. 

Figure 2-4. Matrix transposition via Excels interactive graphical user interface...

The data for the reactions of potassium cyanide with benzyl halides at 85 C and 25 C are summarized in Tables I-III and graphical representations of these data are shown in Figures 1-3. The reactions carried out at 85 C were followed to 70% completion, while those at 25 C were followed to 50% completion. In general, excellent first-order kinetic plots were obtained. Each point on the graphs represents an average of at least three kinetic determinations. It is interesting to note that in the absence of added water (solid-liquid phase transfer catalysis), the rates of benzyl halide disappearance were more accurately described by zero-order kinetics. 

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