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36

Using Snow's Cholera map story. When John Snow mapped the Cholera outbreak in London, he noticed that most cholera cases appeared near certain water pumps. After these pumps were closed or cleared, the cholera outbreak stopped. This is how daddy's work can help save the world! In general, I always like to explain using images and vivid examples. A ...


24

Kids often learn well through experiences, so I'd take them geocaching, and show them how the coordinates helped us find the cache. Afterward, I'd display the track in Google Earth or QGIS, and show them maps overlaid with our trail. Finally, we could calculate how high we climbed to reach the cache using a DEM, or display other data like rainfall to ...


19

Vector Data Advantages : Data can be represented at its original resolution and form without generalization. Graphic output is usually more aesthetically pleasing (traditional cartographic representation); Since most data, e.g. hard copy maps, is in vector form no data conversion is required. Accurate geographic location of data is maintained. Allows for ...


15

Geospatial, geographic and spatial are used interchangeably to mean data with a spatial component, probably on the surface of the earth. The reasoning behind the portmanteau geospatial is that spatial alone is too generic: any three dimensional space qualifies, and geographic is too specific: you could use the same methods for manipulating martian data. ...


15

You have your shape files, which the web browsers cannot read if you put them on a server somewhere. A user could download them and view them in an application but that's not what you want. So this is where GeoServer, MapServer, OpenLayers, PostGIS come into play. You would use PostGIS to store the data in your shape file as it's a spatial database. ...


14

There is one blog post from Michalis Avraam that explains essential skills to succeed in GIS career which I think is well written. You will probably find lot of good advices there.


14

A standard term is geodetic coordinate system. However, the market leader in GIS software tends to invent new terminology with each new release of its flagship system, and by virtue of gaps in fundamental training by most of its users (or just plain enthusiasm for new words), this terminology quickly gets adopted by the majority. For example, "Geographic ...


14

A more complete list (the first answer mainly refer to OpenGeo stack, that is excellent, but there are plenty of other options out there): User Interface OpenLayers GeoExt (based on OpenLayers) MapQuery (based on OpenLayers) Leaflet Polymaps Mapstraction Modest Maps Wax Map Services MapServer GeoServer Mapnik FeatureServer QGIS Server Web ...


13

Some starting points to consider: PostGIS in Action should be your first resource PostGIS section of excellent 'Introduction to an Open Source Geostack' workshop Materials from BostonGIS webpage Also, for general introduction to PostgreSQL I quite enjoyed 'Beginning Databases with PostreSQL' book by Matthew & Stones.


13

This illustration stuck with me, and helps me remember at the most basic level what precision vs. accuracy is.This is the source of the image, also containing a little more context. In general, Precision is the how close your grouping of measurements are. Accuracy is how close your measurement is to the actual measurement in the real world. Blah238 is ...


12

Well I just talked about it with my 11-year old and he understood but was unimpressed. Me: "Imagine you have a map of our city and you want to colour it by income" Him: "But isn't that money? How does that become colour" Me: "Perhaps I decide that high income is green and low income is red and incomes in between are colours in between green and red" ...


12

Pixels vs Coordinates When I think Raster maps, my first thought is satellite imagery. Almost every pixel in a detailed satellite image of a urban area could contain unique information. A single tile in a web map (typically a variant of Mercator loosely referred to as "Spherical Mercator" or "Web Mercator" and supported by Google, Bing, Yahoo, OSM and ...


12

Personally, for the cliff's notes I find the ESRI ArcGIS desktop software help system useful, and and also the ESRI book Understanding Map Projections, its first 30 pages are not unlike a short textbook, followed by ~70 pages of appendix on individual projections, their uses, strengths, weaknesses, etc. From these, you'll quickly understand all the pieces ...


11

I like Chris Garrard's Python for Geoprocessing course materials. http://www.gis.usu.edu/~chrisg/python/2009/ Personally, I find programmatic manipulation of OGR/GDAL to be indispensable. With respect to finding the best fit for you, consider the software or geostack you wish to be most expert in (like ArcGIS, QGIS, PostGIS-GeoServer-OpenLayers), and then ...


11

I would not compare GIS to a programming language. A programming language is a tool that can be used to define your business process. "Perform these steps in this order, making some decisions as you go." GIS is more abstract; rather than being a tool to define a process, it's an entire branch of tools and methods that manipulate data that have location. ...


10

I'd look into geoPDF it allows embedding a georeferenced data in a PDF and can handle everything you've asked for. I'm not sure on the ins and outs of creating one, but might be somewhere to start from? Linky : http://www.terragotech.com/products/terrago-toolbar


10

VB.Net Add-Ins for sure. The ESRI walk-troughs will get you on the way. I've been using VB6 and VBA for years and personally I find VB fairly intuitive. Of course VB .Net is an entirely different animal but the add-in structure is relatively simple to learn and deploy. I just took a technical workshop in ArcPy at an ESRI conference and I have to say that I ...


9

Don't start with C++ and GIS without learning software development first. It's just too much. Python is a good place to start regardless of what GIS platform you go with later. There are a lot of books, websites and training materials available and a lot of colleges use python as an introduction before going on to the heavy duty programming languages, like ...


9

I'd certainly go for PDF, and use FME to create it - with FME you can turn any spatial data into a 2d or 3d PDF. See these examples: http://www.fmepedia.com/index.php/Adobe_PDF The display images I'm not so sure. You can create links on a PDF, but if they aren't connected to a network that doesn't help. However, I bet you could write the images separately ...


9

Ahhh, the dreaded 'decimal minutes'... I think that different people are comfortable with different formats based on the areas that they work/play in. If you plan to use the coordinates to create spatial features, I would store them in decimal degrees (or as spatial features). Computers don't deal well with Sexgesimal numeral systems. (Funny that our ...


8

My way to find PostGIS was http://bostongis.org/?content_name=postgis_tut01#20 there is three parts of the tutorial. I really like it. Then I have to mention: http://postgisonline.org I have tried to build a way of trying spatial SQL queries online. There are a very few tutorials there: http://postgisonline.org/tutorials anyone can write a tutorial and ...


7

Take a look at Portable GIS: provide beginners with a ready-installed and configured stack of open source GIS tools that would run in windows without the need for emulation or a live cdemulation or a live cd i.e. You can have it up and running on a USB stick. Very handy for workplace environments. It has on it: PostgreSQL (version ...


7

I doubt it. Since the length of a sloped road would be sqrt(1+x^2)-times the length of the flat one (where x is the slope). For low values of x, this is roughly 1+1/2*x^2, which is rather low, eg. for a 10 % slope, you get an error of 0.5 %. Not considering the actual lane you drive probably has a similar error.


7

Answering a question about the difference between a projection and a datum, Bill Huber links to his article in the Directions Magazine where he gives introductory explanations of georeferencing, datums, spheroids, and the like. As short and concise as it can be!


6

I've attended two ESRI UCs and got to go to the ESRI Dev Summit in Palm Springs this year. If you are drinking the ESRI Kool-Aid, then the Dev Summit is your best bet over the UC, in my opinion. Everything at the Dev Summit is developer-centric. Code everywhere. ESRI engineers everywhere. The engineers are at the UC as well, but not in such a massive ...


6

I usually say "Information that has position - perhaps an address, perhaps coordinates like you would get from a GPS" It's not exact nor is it complete but I find it's usually all a non-professional can handle before they stop listening to you. The explanation usually gets them to ask a question too, which helps with understanding. If they ask how an ...


6

A good start can be the PostGIS Manual edited by Paul Ramsey. document download URL: http://www.geoconnections.org/developersCorner/devCorner_devNetwork/meetings/2002.05.30/postgis.pdf


6

From the ESRI website: http://www.esri.com/getting-started/executives/index.html "GIS provides critical tools for success and efficiency. As an executive, you are presented with a high volume of complex data every day. GIS helps you Organize your information and knowledge. Make informed decisions. Improve communication. Increase efficiency. Share ...


6

I'd suggest starting from http://www.w3.org/Mobile/posdep/GMLIntroduction.html. If you're planning to work with application schemes in INSPIRE, you'll also need a thorough understanding of XML and XSLT (Extensible Stylesheet Language Transformations). I think the task doesn't require in-depth understanding of UML. You'll have to be able to read it. Anyway, ...


6

It sounds like you are looking for a way to express this to non-technical people, perhaps? You could use an analogy to two childhood items, graph paper and a connect-the-dots puzzle. Each square in a sheet of graph paper corresponds to a raster cell, so imagine coloring each square in, or putting a number in it. Vector data is a connect-the-dots puzzle. In ...



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