[MUSIC] Welcome to the first lesson on symbology and cartography. In this lesson, we're going to discuss some facets of good design. I'm going to show you different types of symbols used in ArcGIS and how to symbolize based on attributes. Before we start talking about symbology, I want to start by saying that design is hard, at least for most of us. If you're a scientist or an analyst or business manager or utilities worker, you may not have had much experience designing informational graphics and illustrations for other people to use. Design has to require a whole different way of thinking than what we're used to. And you should give yourself some credit as you get started because it's difficult for most of us. One thing to keep in mind as you get started with design is that you won't take good design for granted when you see it because you will know the effort and attention to detail that went into it. As you start working with maps the primary thing you should ask yourself is, what is the purpose of my map? Keeping your purpose in mind at all times helps you to create that polished map by making sure you don't add extraneous things that confuse the viewer. There's an old saying in design that you should remove everything you can in your design until your design doesn't work anymore, and then add that last item back in and then you're done. Design is a classic, less is more type of discipline. One way to keep your purpose in mind is to always consider who your audience is. By imaging your viewer you can make sure that you include things that are important to that viewer and leave out the things that are not. Another way to do this is to make sure that you set an appropriate scale that illustrates the phenomenon that you're trying to show. One other important consideration in design that we constantly rely on but don't always think about, is whether or not a design uses colors, patterns, and symbols that are intuitive to us. If I'm trying to depict something that is good versus bad, using the colors green and red is probably good for most audiences. Conversely, if I'm not showing something that is a gradient of good to bad, I should probably not use green and red. And instead use a more neutral color, so as not to subliminally influence my viewer into thinking that one thing is good and the other is bad. That last example is a good representation of how you can influence your viewer either intentionally or unintentionally. You may be familiar with the famous book called, How to Lie with Statistics. The general concept of which is that you can create a statistic to prove something in many different directions from the same information, and that choice of statistics matters. What you may not know is that there's a similar book called, How to Lie with Maps regarding the same phenomenon in cartogrophy and symbology. From one data set, you can often construct very different stories in the mind of your viewer. Most of this is accidental rather than malicious. So it's something to pay close attention to when you're creating your maps. Take a look the images of California I'm showing you. This data is from the same data set and using the same variable. But I just sued a different built in way of breaking the data into groups. It's the easiest mistake to make to misrepresent my data, because often there's no best way to display it, just ways that illustrate different themes. So, for maps symbology is how we choose to make symbols and display our data to the viewer. There are many ways to do that but I want to point out a few of the ways that we do that for polygon data in ArcGIS. We can simply show the outlines of our polygons as single symbols or we can group our symbols into categories visually by color. We do this by ArcGIS to take the values from an attribute, and create groups with them, and then assign a color to each group. This might be a good way if we are trying to display dominate land cover or demographic information such as political party affiliation. We can also choose to display our symbols quantitatively with continuous symbology. This works similarity to how we used categorical symbology, and it uses an attribute in our attribute table to create groups of our data. The difference here is that instead of taking each individual value and assigning it a color, we create ranges of values from our continuous data and assign colors to those values. This might work well for displaying emergency calls in an area, vote totals, economic information, or something of that sort. And the last major type of polygon symbology is when we create graphics or figure symbols. This is where we can create charts and figures and overlay them on top of our polygon boundaries so that you know which figure information corresponds to which area. Again, what you choose to use depends on your data, the purpose of your map, and your audience. So, that's a basic introduction to design considerations and symbology in ArcGIS. In the next video, we are going to actually take a look at some real-world maps to see how professionals apply these considerations.
