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- Newsgroups: sci.math.stat
- Path: sparky!uunet!spool.mu.edu!umn.edu!csus.edu!sfsuvax1.sfsu.edu!emclean
- From: emclean@sfsuvax1.sfsu.edu (Emmett McLean)
- Subject: AGSS (A Graphical Statistical System) <> written in APL2
- Message-ID: <1992Nov24.043803.20066@csus.edu>
- Sender: news@csus.edu
- Organization: San Francisco State University
- Distribution: NA
- Date: Tue, 24 Nov 1992 04:38:03 GMT
- Lines: 201
-
- This a promotional post I'm making it on behalf a some
- fellow APL programmers I know through APLBUG group in
- the Bay Area. For those of you who have never heard of AGSS
- this is a brief account of what it has to offer. At the
- bottom of this post is the name and address of Lewis Peters,
- who would like to teach a course in using AGSS if there is
- sufficient interest. Feel free to contact him. (What follows
- comes from me and is not affiliated with SFSU in any way.)
-
- A Graphical Statistical System (AGSS)
-
- System Overview
- ---------------
- AGSS is an IBM interactive system for 2 and 3 dimensional scientific
- engineering graphics, applied statistics and data analysis. It runs
- under APL2 on a 386 (or higher) PS/2 on a RISC System/6000, or on a VM
- host system. (See requirements below.) It is an easy to use, menu
- driven system with on line helps for each entry field and extensive hard
- copy documentation. It is widely used within the Research, Development,
- and Marketing operations of IBM.
-
- 2/D Scientific Engineering Graphics
- ------------------------------------
- X,Y plots are easily produced using default options. Easy access is
- provided for the control of all plot characteristics. These include line
- types, symbol types and size, axis labels, plot headings, tic marks,
- axis scales and grid characteristics. Further, the colors of all these
- elements can be separately controlled. Plots can be annotated and
- legends easily created. Over 30 fonts are available as is the ability
- to produce super and subscripts. Hence, publication quality as well as
- working graphics are readily produced.
-
- 3/D Scientific Engineering Graphics
- -----------------------------------
- The system contains a full range of 3/D plots. They include surface
- plots, contour plots, surface plots combined with projected contour
- plots, trajectory plots, scatter plots, and parametric Y,Z plots.
- Complete controls exist for all plot characteristics.
-
- Curve Fitting
- -------------
- Very powerful screens (menus) exist for applying both linear and
- nonlinear least squares to the fitting of curves to data. For the
- linear case a number of commonly used options are provided as well as
- the capability of fitting a linear combination of any set of user
- specified functions. A wide range of confidence, tolerance, and
- prediction intervals can be generated. Weighted and robust options
- exist. Residuals can easily be plotted and their distribution
- analyzed. Finally, other linear approaches including smoothing splines
- and LOWESS smoothing are available.
-
- The non-linear screen will fit any user specified function of any number
- of parameters. Optionally, upper and/or lower constraints can be placed
- on the estimated coefficients. All the features mentioned in the
- connection with the linear case are available.
-
- Surface Fitting
- ---------------
- Linear least squares can be applied to the fitting of surfaces to 3/D
- data. Bivariate polynomials are explicitly provided but a linear
- combination of any user provided functions can be fit. Coefficient
- confidence intervals and residual analyses are available.
-
- Descriptive Statistics and Exploratory Data Analysis
- ----------------------------------------------------
- AGSS provides the following capability: bar charts, pie charts,
- skyscraper plots, scatter plot point identification, symmetry plots,
- quantile-quantile plots, histograms, empirical CDF's, empirical
- densities, percentile plots, box plots, bivarite histograms, and
- bivariate empirical densities.
-
- Reliability Analysis and Distribution Fitting
- ---------------------------------------------
- This set of functions is used to fit univariate distributions to data,
- provide graphical comparisons of the empirical and fitted
- distributions, estimate the parameters of the distributions, and produce
- goodness of fit statistics. Any of 18 distributions may be specified.
- For the five distributions commonly used in reliability analysis;
- exponential, extreme value, lognormal, normal and Weibull; the system
- accepts both censored and interval data.
-
- Plots and tables for the following functions of the fitted distribution
- are available: density, CDF, survivor, hazard, cumulative hazard,
- reliable life, average hazard rate, and interval failure rate. In most
- cases, pointwise confidence bounds are provided.
-
- Accelerated Life Testing
- ------------------------
- Four screens are provided for simulating and fitting constant stress and
- step stress accelerated life test models. Tests of model hypotheses,
- residual analyses and survival analysis (for prediction purposes) are
- provided.
-
- Regression Analysis
- -------------------
- An ordinary least squares screen includes all the common model building
- algorithms (stepwise, all possibles subsets, best subset of a given
- size, etc). It also includes extensive residual analysis and diagnostic
- capabilities as well as detailed analyses of stepwise procedures. There
- is a heavy emphasis on graphical output. Other screens implement
- non-linear, robust, lifetime, and ridge regression.
-
- Design of Experiments
- ---------------------
- This component provides very extensive capabilities for designing and
- analyzing 2 level complete or fractional factorial experiments.
- Additionally, there are options for blocking, replications within blocks,
- center points, and randomization. The analysis phase includes
- probability plots, residual analyses, interaction plots and the analysis
- of means.
-
- Quality Control
- ---------------
- The quality control component consists of five screens for the design
- and implemention of Shewhart and cusum control charts and the analysis
- of means. The design screens enable you to design control charts having
- specified statistical properties in terms of average run length or
- operating characteristics. Each of the control chart screens plots the
- control chart, and provides a table of summary statistics. The
- Analysis of Means screen provides the ability to plot Analysis of Means
- control charts for any number of factors.
-
- Time Series Analysis
- --------------------
- There are eighteen screens for the analysis of time series data, the
- construction of time series models, and the use of these models for
- forecasting. There is a complete implemention of Box Jenkins univariate
- techniques including automatic ARMA model selection and transfer
- function models. Spectral estimates can be generated both through
- periodogram smoothing and through the fitting of ARMA models. Other
- capabilites include acf, pacf, and ccf estimation, and Holt Winters
- forecasting.
-
- Work Management Utilities
- -------------------------
- AGSS has a set of catalog screens that enable you to review, execute,
- edit and document your screen responses, APL variables, and APL
- functions. It has a file management system that allows you to store and
- retrieve these objects efficiently. In addition it has a diary
- facility, which when turned on, will keep a record of all screen
- executions. Thus the system has extensive utilities for the effective
- and efficient management of work units.
-
- Generating Hard Copy Output
- ---------------------------
- PostScript files of graphics output can be generated on both the PS/2
- and RS/6000. Under VM and GDDM, a wide variety of graphics output files
- are available.
-
- Relationship to APL
- -------------------
- Minimal familiarity with APL is required. Specifically, the user should
- understand the basic concepts of an APL variable, an APL array and an
- APL function. More experienced APL users can exploit the power of the
- language but this is not necessary to make effective use of the system.
- AGSS is synergistic with APL in that the screens entries can be APL
- expressions and , in that, the AGSS screens can be used as high level
- building blocks within the user's own APL functions. This gives the
- system a unique extendibility.
-
- AGSS Requirements
- -----------------
- PS/2: 386 (or higher) with coprocessor, 4MB memory, 15MB hard disk, VGA
- Display, DOS 3.3 or higher, APL2/PC(Release 1.02).
- RS/6000: 15MB hard disk, AIX 3.1 (or higher), APL2/6000.
- VM: APL2 1.3 GDDM Release 4 or higher, 4MB Virtual Machine, 20 3380
- cylinders, GDDM Terminal with APL keyboard.
-
- Ordering AGSS
- -------------
- AGSS is an IBM "As-Is" product. It can be ordered through your local
- IBM Branch Office or directly from IBM Research. (To find out the
- location of your local branch office call 800-426-3333.)
- Ask for: A Graphical Statistical System (AGSS)
- (Listed under SWAPPLIC on the HONE System. The branch office must
- request order forms from ASISCODE at RHQVM21.) To order directly from
- IBM Research send a check made out to "IBM Corporation" to Peter Welch,
- IBM Research Center, PO Box 704, Yorktown Heights, NY 10598. If you
- have a problem ordering AGSS or would like more information, call Peter
- Welch at 914-784-7560 or Alvin Blum at 914-784-7563.
-
- AGSS Prices: PS/2, $250; RS/6000 $5000; VM, $2500. AGSS is offered with
- a 30 day trial period.
-
- Ordering APL2
- -------------
- APL2 for the RS/6000 and VM are IBM Program Products and are ordered
- through your local IMB Branch Office. To order APL2/PC, call
- 800-426-2468 and order Part No. 6242936.
-
- Introductory Course
- -------------------
- Peter Lewis's address and numbers:
- :nick.LEWISP :notebook.INET
- :name.Peter A.W. Lewis
- :phone.408:646-2283
- :addr.Department of Operations Research;
- Naval Postgraduate School;
- Montery, CA 93943
- :CSADDR.1526P%NAVPGS.bitnet@cunyvm.cuny.edu
-
-