Year
2008
|
|
| 22
August
|
A long time without updates! Most of our
work in the interim has appeared on internal Web sites at Penn
State, Haverford College, and Bryn Mawr college, and in the
scientific literature. Some of it will be making its way onto
these pages in the near future.
A recent presentation on spatial analysis, with a
focus on crime mapping, has been added to our GIS
Presentation section.
|
Year
2003
|
|
| 21
May
|
As a part of June's World Congress on Risk
in Brussels, there will be a day-long tutorial workshop on using
imprecise probabilities in risk analysis on 22 June 2003 (Sunday).
This tutorial will introduce interval-valued
probability and imprecisely specified probability distributions and
will review their uses in risk analysis. It will address the
approaches of interval probabilities, probability bounds analysis,
Dempster- Shafer theory, robust Bayes methods, and the general
theory of imprecise probabilities.
See the website http://www.ramas.com/ipbrussels.htm
for more details.
|
Year
2002
|
|
| 8
June |
The short illustrated article
on Linear Kriging is back
(Comcast had unilaterally demolished the page that was hosting
it). See an overview of all the articles posted on our pages at Articles. |
| 23
April |
"Steganography" is
the art of hiding messages in other works such as images. It is
useful not only for secret communication but also for protecting
intellectual property and data compression. Techniques
to hide messages in raster images are well known, but methods to hide
messages in vector images--the format commonly used for GIS data--are
not well developed. Our article on Vector
Steganography changes this by proposing two techniques and
presenting ArcView software to implement them. A parallel
article by Bill Thoen provides an overview and offers MapInfo
software. Four sidebars to our article explain the details. |
| 16
April |
XSect
version 1.50 has been released. It includes two new
general-purpose utilities, the coordinate grid maker and the trace
maker. |
| 19
February |
We continue to decrypt
encrypted ArcView scripts to help developers and users rescue lost
Avenue source code. See the ArcView Encryption
page for more information. |
| 14
February |
XSect
is an ArcView 3.x add-on that creates cross-section diagrams of
point data. Created as a custom application for a client (who uses
it very effectively for assessing soils investigations), it has general
applications wherever irregularly-spaced data are associated with
varying depths or elevations. |
| 28
January
|
Many more links now appear on the GIS
articles page. |
| 27
January
|
See our Free Software pages for two more
contributions: SaveWin lets users restore previous window
positions and sizes in ArcView; Ave2HTML reformats Avenue
source code to make it more readable. The Cartogram!
extension has also been improved to allow greater control over feature
sizes. |
Year
2001
|
|
| 11
December |
The Report
joins and links software documents all join and link relationships among
tables in any ArcView project file. |
| 4
December |
Our growing References
page now includes telegraphic reviews of books we recommend. |
| 4
December |
Visit our Clients
page for lists of representative clients and software purchasers. |
| 27
November |
We have created a new page of
links to the valuable (and free) data that we host. Visit the Data
page for more information or, from our home page, follow the Free
Software|Data links. |
| 24
October |
Our Cartogram! extension
for ArcView 3.2 and later provides an interesting way to visualize
quantitative data. |
| 28
June |
A reader asked how to
create
arrows among features on a map to represent flows (of people, resources,
or whatever). See his maps and learn how they were created at Represent flows (arrows) on a map,
available on our popular GIS How to...
pages. |
| 26
June |
A reader wrote, "I have a DEM of the Red River in Manitoba and I
would like to simulate a flood." See his solution and learn how it
was done in GIS at Simulate a Flood,
available on our popular GIS How to...
pages.
|
| 12
June |
Visit Foreign Language Follies
for a very amusing example of how technical terminology is (or is not)
propagated around the world. |
| 22
May |
Life and CA
is a short article responding to a reader's question about our
implementation of a cellular automaton in map algebra. |
| 9
May |
Taking
risks, Reaping the Benefits describes in a clear forthright manner
how techniques of quantitative decision making find a fundamental
connection between environmental management issues and financial
decisions. |
| 3
May |
For the last five months most of
our web-building efforts have been directed at developing pages for a
college course in environmental
statistics. We are pleased to announce their availability. |
| 22
March |
We have posted a new article,
Estimating Markov Transitions, about analyzing land cover
change with imagery. This appeared in the Journal of Environmental
Management in 2001. |
| 5
March |
ArcView users: subscribe
to the new ArcGIS and ArcVB discussion lists for help with migrating to
the Arc 8 environment. Detailed information is available at www.directionsmag.com/Discussion. |
| 1
February |
We have posted a paper
("PCBs in Pipes") that analyzes the performance of a
statistical test proposed by the US EPA. Although the EPA has
since abandoned its position, the test (which is based on the
exponential distribution, rather than the lognormal distribution more
familiar to environmental analysts) remains of interest. The paper
is self-contained, developing the theory of the test from first
principles and thoroughly analyzing its operating characteristics. |
Year
2000 and before
|
Please see Old news |
