Trend analysis

- [Instructor] When you go out hiking in a new place, … it's nice to have a path … to help you get where you're going. … It's also nice to know that the path … might actually take you to some place you want to be, … so how can you see where you're going, … and how long it's going to take you to get there? … Well, as a data scientist, … your job is to figure out the path your data is on, … so you can inform decisions … about whether to stay on the current path, … or whether changes need to be made. … The most basic way to do this is with trend analysis, … and it starts by plotting a line. … Simply make a graph of the changes over time, … and then connect the points … to make a clear line of one kind or another. … Now, when you're doing the analysis, … you have to be worried about something a little different … from other analyses we may have looked at, … and that's something called autocorrelation, … or self-correlation. … The idea here is that every value is influenced … by the previous values, more or less. …