About this video
The video works through three scatter plots, deciding whether a good line of best fit exists. For the first two, any line would mean ignoring groups of points, so there is no good fit; the third has a clear trend that a line fits well.
You'll be able to
- decide whether a scatter plot has a linear trend.
- explain why you can't ignore points to make a line fit.
- place a line of best fit that follows a clear trend.
Key words
- line of best fit
- A straight line drawn to show the overall trend in a scatter plot.
- linear correlation
- A pattern where the points roughly follow a straight line.
- trend
- The general direction the data points follow.
Transcript
Find the line of best fit, or mark that there is no linear correlation. So let's see, we have a bunch of data points, and we want to find a line that at least shows the trend in the data. And this one seems a little difficult because if we ignore these three points down here, maybe we could do a line that looks something like this.
It seems like it kind of approximates this trend, although this doesn't seem like a great trend. And if we ignored these two points right over, we could do something like maybe something like that. But we can't just ignore points like that. So I would say that there's actually no good line of best fit here.
So let me check my answer. Let's try a couple more of these. Find the line of best-- well, this feels very similar. It really feels like there's no-- I mean, I could do that, but I'm ignoring these two points. I could do something like that, then I'd be ignoring these points.
So I'd also say no good best fit line exists. So let's try one more. So here it looks like there's very clearly this trend. And I could try to fit it a little bit better than it's fit right now. So it feels like something like that fits this trend line quite well.
I could maybe drop this down a little bit, something like that. Let's check my answer. A good best fit line exists. Let me check my answer. We got it right.
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