10 Things When Making a Map. What makes a good map? When done well, a map is a vehicle for effective communication. There are many cartographic principles to help guide effective map making. Below are ten common considerations that all cartographers should incorporate as part of their map making process. This list isn’t meant to be a comprehensive list but rather a starting point of things to contemplate. Different cartographic presentations will require additional points of consideration and techniques. 1. Geographic Bounds The extent of the geographic area mapped will affect a whole slew of cartographic choices from the map projection used to data and symbology choices. 2. There are two main reasons to include data on a map: to support the subject matter of the map and to provide orientation (e.g. streets, cities, points of interest). 3. The choices of symbology can make or break a map. Consider the intended audience of the map when selecting design choices. 4.
India national highway map. 5. 6. 7. 8. 9. 10. When Maps Shouldn’t Be Maps. Often, when you get data that is organized by geography — say, for example, food stamp rates in every county, high school graduation rates in every state, election results in every House district, racial and ethnic distributions in each census tract — the impulse is since the data CAN be mapped, the best way to present the data MUST be a map. You plug the data into ArcView, join it up with a shapefile, export to Illustrator, clean up the styles and voilà! Instant graphic ready to be published. And in many cases, that’s the right call. For example, census maps of where whites, blacks, Hispanics and Asians live in New York City show clear geographic patterns, answering questions like “What areas of the city are more segregated?” Or “Where is there more diversity?” You can see how Prospect Park is a stark dividing line, with largely white areas west of it, and largely black areas east of it.
Maps also a terrific way to let readers look up information about specific places. 1. 2. The case against map visualisations [CSIRT Foundry] 31 January 2012 One of the most abused forms of data visualisation in information security today is the world map. During this post, I’ll explain how making maps our “go to” visualisation limits the insights we can show. But it’s a natural fit Certainly, maps seem like a natural choice for network data. Or perhaps not. Visualising your data to increase understanding is a great idea, but I’m going to convince you that a map is often not the best way. Why not maps? In the non-Internet, meatspace world, distance matters. On the Internet, however, distance is not a factor we’re usually interested in. Once a PC is infected with a new worm, what factors impact its spread? But everyone knows what a map is!
Everyone is familiar with maps, but that doesn’t always make them the most effective choice. Before you think about that, think about this. Map constraints 1. Let’s say that you have a worldwide malware infection. Some questions: How many countries have infected computers? Pencils down. 2. 3. The Art of the Basemap. “Graphical elegance is often found in simplicity of design and complexity of data.” – Edward Tufte Data visualization is the art of quantitative story telling. The story of data about places is commonly told on maps. The purpose of a basemap is to provide the appropriate backdrop for telling a really compelling story.
The basemap provides the stage and setting for the story, while data—tied to specific geographical coordinates– provides cast and plot. We’ll have more to say about cast and plot later, but first let’s talk about stage and setting. The basic elements of a base map are water, land, nature, roads, buildings, place labels and icons. Each of these elements can be designed to stand out prominently for map reading, or they can quietly reside in the background providing subdued context for story telling. Take, for example, the following illustration of county voting data from the 2008 presidential election. 2008 presidential election results by county Gray style (depicted below), Creating Maps for Wikipedia and Printed Materials with ShareMap.org. The availability of simple online mapping tools (such as what Google Maps offers) allows those with limited geospatial technical knowlege to design simple maps via a web browser without using any external professional tools. These tools open up mapping to anybody who wanted to create a map of their neighborhood, holiday trip, and any other geographic idea that came to mind.
Creating geographic content become easy, but exporting that content to other programs is still very difficult or even impossible. Even when the data is in KML format, there is no easy way to use it in creative tools like Adobe InDesign. The problem is that KML contains geographical coordinates (latitude, longitude) and vector graphics requires absolute coordinates – x,y. Data have to be projected in some way readable to graphic programs, but such projection and conversion mechanisms are normally unavailable in typical Web GIS services.
Example: Creating a planned tramway route map using sharemaps.org. Colorbrewer. TypeBrewer. Sensible colours in your maps. If you are creating maps then for goodness sake I was helping some undergraduates with some work the other day, and they decided to use the following colour scheme for representing river depth: Deep water: RedMedium-depth water: Bright greenShallow water: Pink Why did they do this? Well, either they were the default values used by the software they were using (unlikely), or they just chose randomly. Not a good idea. If you look you’ll find a huge amount of literature about this (I should put some references here but I can’t really be bothered at this time at night), and it really makes your maps a HUGE amount more useable if you’re using sensible colours. Deep water: Dark blueMedium-depth water: Medium-blueShallow water: Light blue Why is this sensible?
Isn’t it hard work to come up with nice colour schemes for all of your maps? Plugins and extensions are available for a number of pieces of software to allow ColorBrewer colours to be easily used. Take Care of your Choropleth Maps. Over the last week I had some fun playing with choropleth maps. Thereby I analyzed the following US poverty map, which was recently published at the Guardian data blog: To be honest, the first time I saw this map I didn’t thought much about it. Ok, poverty is highest in south central of the United States, especially near Mexican border.
But recently I used the same data to demonstrate a choropleth map that I created from-scratch and I was really surprised to see a somewhat different picture: Naturally, I wanted to know where the differences come from and spent some time to investigate. Actually, I think there are two big fails in the Guardian map (which was made using Google Fusion tables). Don’t mess around with your class limits The values in the poverty data range from 6.6% to 22.7% and the map shows them divided into five classes.
Note that the fifth class (which shows the poorest states) is blown up while the first class is a bit under-represented. Quite a different picture, isn’t it? Colorblind Web Page Filter. Web colors. Web colors are colors used in designing web pages, and the methods for describing and specifying those colors. Colors may be specified as an RGB triplet or in hexadecimal format (a hex triplet). They may also be specified according to their common English names in some cases. Often a color tool or other graphics software is used to generate color values.
In some uses, hexadecimal color codes are specified with notation using a leading number sign (#).[1][2] A color is specified according to the intensity of its red, green and blue components, each represented by eight bits. Thus, there are 24 bits used to specify a web color, and 16,777,216 colors that may be so specified. Hex triplet[edit] A hex triplet is a six-digit, three-byte hexadecimal number used in HTML, CSS, SVG, and other computing applications, to represent colors. Byte 1: red value (color type red) Byte 2: green value (color type green) Byte 3: blue value (color type blue) Shorthand hexadecimal form[edit] HTML color names[edit] 0to255.
Vischeck: Home. Colour Testing - for Colour Blindness & Deficiencies.