This is the Tricky Part: When Directions Become Difficult

Journal of Spatial Information Science, Number 1 (2010), pp. 53-73

Stephen Hirtle, Kai-Florian Richter, Samvith Srinivas, and Robert Firth

“Automated route guidance systems, both web-based systems and en-route systems, have become commonplace in recent years. These systems often replace human-generated directions, which are often incomplete, vague, or in error. However, human-generated directions have the ability to differentiate between easy and complex steps through language in a way that is more difficult in automated systems. This article examines a set of human-generated verbal directions to better understand why some parts of directions are perceived as being more difficult than the remaining steps. Insights from this analysis will lead to recommendations to improve the next generation of automated route guidance systems.”

Carlos Salmán Receives Esri’s Lifetime Achievement in GIS Award

The Esri International User Conference provides an opportunity to honor individuals and organizations for their exceptional work in geographic information system (GIS) technology. At this year’s 30th Annual User Conference, Esri president Jack Dangermond presented the Lifetime Achievement in GIS Award to Antonio Carlos Salmán Gonzalez, longtime Mexican cartographer and visionary.

“GIS provides the enlightenment and awareness necessary to stimulate the urgent changes needed in Mexico so that its citizens can realize their full potential,” says Salmán.

Salmán has spent nearly 40 years developing mapping projects in Mexico and abroad. He began his career in 1971 as a photogrammetrist with the Commission for Studies of the National Territory (CETENAL), a Mexican government agency.  In 1974, he was awarded a scholarship to the International Training Centre for Aerial Survey (ITC) in the Netherlands, where he completed a postgraduate degree in photogrammetry. Salmán returned to Mexico in 1975 to head the photogrammetry department at CETENAL. Later, CETENAL suspended the production of the country’s National Inventory of Natural Resources project, arguing that it was not cost-effective to continue collecting the information at a national level. Recognizing the immense value of the inventory, Salmán mounted an unsuccessful campaign to continue the project.

Because of his belief in the importance of maintaining a national resources inventory for the country’s economic sustainability, he left CETENAL in 1980 to form Sistemas de Información Geográfica, S.A. (SIGSA) and provide those mapping services he felt were of national importance. SIGSA’s Mexico Project develops national maps using ArcGIS technology at varying scales, from 1:1,000 in urban areas to 1:20,000 in rural regions, which are used for a variety of projects and studies.

“I believe that before Mexico can realize a true understanding and stewardship of its natural resources, we must first achieve what I call the knowledge revolution,” concludes Salmán. “Information does not benefit a society unless it is commonly shared and transformed into social knowledge, which facilitates greater understanding and awareness.”

For more information about the many uses of GIS, visit

[Source: Esri press release]

A Fundamental Change in Science: A Brief Interview with Prof. David Maidment

Q: At the Friday morning closing session of the 2010 ESRI International User Conference, Scott Morehouse invited you on stage for a few minutes to share your experience that week.  Can you share that experience again?

A: Well I already knew a lot about what was going to happen before the User Conference had even started, because I’d worked closely with Jack Dangermond on a paper a couple of months prior to the Conference, and I’d also worked closely with Clint Brown and Scott Morehouse before that.  But when I saw it all come together on Monday at the plenary session, somehow the neurons got connected in my mind and I sent a message to my staff back in Austin—get me an iPad!—while the plenary session was going on.  I now have an iPad.

By Tuesday, the impact of what was happening at the conference was overwhelming, and I went into kind of a vision-lock.  All these ideas were competing in my mind, and I was sitting in a Conference session and suddenly I realized, I’m still carrying a plastic bag.  What is this?  It’s my laundry!  I came out of my hotel room with my laundry bag and suddenly I went into vision-lock and I forgot all about my laundry!

It took me awhile to process it through, but by Thursday, in the Water Resources User Group, I gave a talk on implementing Jack’s vision in Hydro.  I’ve attended the ESRI User Conference 21 years in a row, and I’ve been teaching the Hydro seminar since 1994.  And the 2010 User Conference was by far the most important to me ever.  And why this is so important is because water changes with time.  Because of this, it’s been so inconvenient to deal with it in a GIS framework.  At least up until now.

I woke up Friday morning of the User Conference, and I realized, this is a fundamental change in science.  The implications are just immeasurable.  I don’t think we know where the limit of them is.  And it took me all week to process what happened to reach that conclusion.

Prof. David Maidment speaking at the Friday morning closing session of the 2010 ESRI International User Conference.

Q: You call this a fundamental change in science.  Can you explain in more detail exactly what you mean by that?

A: What’s happened is that time and space have come together—space-time.  Now, that’s been true in science for some time, because you could have spatially continuous arrays like time-varying sea surface temperatures and so on.  But it’s not been true in GIS.  So the fundamental breakthrough here in geographic information science is representing space-time processes on discrete spatial objects.  And that’s a fundamentally new thing that’s not been possible or accessible before.

Q: From a personal perspective, how is this going to change the way you do research?

A: What it means is that we can really bring water into GIS.   We can study the properties of water itself as they vary in space and time, and not just the watersheds, rivers, and aquifers through which water flows.  That is so important for better understanding how water impacts human life and sustains living communities.   Access to water information through the iPad and iPhone are also breakthroughs – water information everywhere, all the time!   Water is so vital to people and we are bringing knowledge of water closer to them.

Dr. David R. Maidment is the Hussein M. Alharthy Centennial Chair in Civil Engineering and the Director of the Center for Research in Water Resources at the University of Texas at Austin.  He can be reached at

Spatial Analysis of Livelihoods of Smallholder Farmers in Striga-infested Maize-growing Areas of Eastern and Southern Africa

International Institute of Tropical Agriculture and African Agricultural Technology Foundation report, January 2009

H. Bouwmeester, V.M. Manyong, K.D. Mutabazi, C. Maeda, G. Omanya, H.D. Mignouna, and M. Bokanga

“This report presents results from a spatial analysis of selected data generated through a livelihoods project in Striga infested areas of Malawi, Tanzania, and Uganda. In addition to mapping spatial patterns on livelihood indicators using Global Information Systems (GIS), the study also compared two interpolation techniques (ordinary Kriging and averaging) of measured values to surrounding locations. Livelihood indicators considered and spatially mapped in this report are related to natural capital, human capital, financial capital, maize growing Striga infestation and livelihood outcomes. Results show that many variables and indicators are clearly related to space. This is especially true in Malawi where many maps show a clear gradient from the “poor” south to the “rich” north. Many other maps in Tanzania and Uganda seem to suggest a similar correlation in space as nearby administrative units tend to have similar values on indicators. Although the survey that generated data used for this report was set up according to socioeconomic criteria and not so much on spatial criteria, the findings show that any economical study can profit from spatial analysis. The report also makes recommendations on how to improve on the collection and recording of geo-referenced data in the farmers’ fields.

“The livelihood project was designed to understand the effects of Striga on the livelihoods of the poor. Therefore, the sampled households were always located in areas known to be heavily infested with Striga. Expansion of areas of interest to areas not heavily infested to assess the effects on the researched indicators is recommended. This study indicates the power of GIS in exposing the socioeconomic consequences of a biological threat (Striga in this case) on smallholder farmers via a set of quantifiable indicators. Therefore, it can be said that databases designed for socioeconomic purposes can be very useful in spatial analysis. Two methods of interpolation were applied that allow socioeconomic properties to be predicted for unvisited sites. The results indicate that applying the two methods generate a spatial correlation in many of the economic indicators.”