Now, one of the key outputs and deliverables that data analysts create, are those insightful reports you present to your audience. In this data visualization module, we'll cover a little visualization theory and best practices, and then we'll introduce Google Data Studio, as one of the visualization tools in your toolkit for creating those actionable reports. Now, visualizing data is another key skill that's part of the data analyst's skill set. And the two major reasons why visualized data is so important; one is probably pretty obvious, building those interactive deliverables and charts and graphs for your audiences, is just a great tool to be able to display those insights. But often the first one that comes to mind for me as a data analyst, is if I don't know those insights off the bat, and I want to explore my data sets, a lot of times the visualization tool if you're a more visual thinker or learner can help uncover those insights a little bit more clearly than just poking around at your data set with SQL. And clearly use case resource before was in the previous course looking at cloud data prep. When you're in the transformer and you see those histograms at the top for the frequency of data values in that particular column, you get a very clear visual picture of a lot of that underlying data. What are the key trends? What are those anomalies that you see just by seeing those bar charts visually? So visualization can do a lot of things. So four quick things that we are going to highlight, you can spot those hidden trends, you can interact with the data set, so you can tell a story that has multiple pieces. So, say you start with a time series data, and then you just click into one of the anomalous spikes or troughs in the data and you drill down into those details very visually. So it's a natural tool to let your audiences follow that cohesive story throughout the flow of your explanation. And of course, it can be very visually aesthetically pleasing as well, building those dashboards and conveying those insights in a very fast and effective manner. And lastly, if a lot of your data is already in big query, putting a visualization tool on top of it like, Google Data Studio will naturally get all the performance benefits of having your data and your queries processed in big query, and then displayed and rendered quickly on the front end in a visualization tool. So no lecture on data visualization will be complete without talking a little bit about visualization theory. So as I mentioned before, visualization is both an art and a science. So here we're going to get a little bit of the science of what our brains perceive when you look at a beautiful visualization. In this particular case, we have a stimulus where we have a cat. Your eye Immediately recognizes it and says, "Hey, I've seen that before, that's a cute little kitten." And your brain automatically says, "Hey, I've seen a thousand of these before, I immediately know without thinking that it's a cat." Now when you actually get into machine learning, it's actually a little bit harder for machines to have that intuition. Intuition is extremely hard to build in for a computer. Whereas as humans, we're built with a lot of that, what we call pre-attentive processing, where we can immediately recognize things. Now, what does that mean for your data visualizations? It means you can effectively cheat the brain by using common human intuition to not have the brain do a lot of work. As humans we have evolved to not do a lot of mental processing, we want to make those snap judgments very quickly, and then only tap into that really focused thought power when it's required. So let's take a look at an example together. All right. So take a few seconds and count all the fives that are present. This is probably one of the hardest exercises that you can do as part of the specialization. You're looking at it? All right. Did you get them, or are you still looking? Now, if you counted 16 fives in the 10 seconds that I gave you that's absolutely amazing, must be like a speed reading level. For the majority of us myself included, It's very, very hard to pick out from this noise of numbers here, this very crowded visual what those fives are. Now, the metal point here is that, this super focused processing that our brains have to do. For majority of us, we we were reading from left to right and serially scanning every single row and counting out all those fives and keeping track of them. Now, there has to be an easier way to do that and naturally you might expect we could do something like this. Now count the fives. How about this time around, was it much easier? Think about what your brain actually did to count those 16 and why it was much faster for you. So on the surface you might say, well, you bolded the fives and that made them a lot easier to see. Well, that's absolutely true. Let's think of the theory behind that. Right? So, in my mind, bolding enabled me to kind of visually cluster those fives into small different chunks and quickly count them out and then pick them. And the two things that stand out from a visualization theory perspective is, when you contrast certain elements, you highlight the focus, and it allows us to treat all the other numbers that aren't fives as background noise that we can safely ignore. So in essence, it saves your brain's time by applying a prioritization saying, "This is what's important, and this is what you should focus on." And immediately our brains can jump at the task and say, "Bam! Bam! Bam! These are all the elements that I actually care about, let me ignore 80 percent of the rest as visual data. We can take this yet a step further and continuously add more, what we call visual encoding on these particular elements that we want to add focus. So here we introduce an element of color where you can further highlight the elements that you want folks to focus on, and it gives it greater attention to what you're calling out as those key points. Now, there's a variety of methods that you can use to "cheat" the brain, and then really tap into that fast processing time, that instant decision making that we as humans have developed over the years. Now, you can mess around with things like, the orientation, the shape and the skew, the length of a certain attribute, the size of the mark on the page. Maybe some elements are curved and some aren't. You're adding things like a box around it, changing the intensity or the hue, moving around in the positioning or even adding things like a motion element to it as well. So, all of these will help the brain focus in on what's important. And then leveraging these and potentially in combination and in concert with each other, will really help make your visualization stand out and ultimately convey that message very quickly, without your audience having to stare at your screen and really focus hard.
