The basics of geospatial analysis

Before we jump into the fun stuff, we will cover some basic concepts. This will give context to how the analytics work behind the scenes.

Welcome to Null Island

If you have devices that report GPS location data, you will soon start to notice that many are visiting an area off the west coast of Africa. A new vacation destination, perhaps? Turns out this is a place called Null Island. If you have not heard of Null Island, it is located at precisely 0 latitude and 0 longitude. There is even a tourism website for it where you can get to know the culture and buy a T-shirt, as shown in the following screenshot:

Null Island location and website. Source: www.nullisland.com

But the place does not exist; it is an inside joke in the geospatial community. Missing coordinate values or null values are stored as 0 and 0 (latitude and longitude). Besides it giving insight into the sense of humor of the geospatial community, Null Island helps to introduce a key concept for geospatial...