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scatter graph relationship/ dependence problem

I`ll attach a pic of the scatter graph most likely as a reply to this thread. The X variable is along the x axis and is plotted against the Y variable (on y axis). The question gives 3 options as to which are correct: There appears to be a linear relationship between X and Y; there appears to be some sort of relationship between X and Y but it is not linear; there appears to be almost no dependence of X on Y. I think clearly there is no linear relationship (cor. coefficient is 0.005609466), but there kind of seems to be a relationship, Y values seem to gravitate towards, the X axis. But my biggest question is how a scatter graph is able to show dependence of one variable on another? Thanks for any help.
scatter graph is here
scatter graph.png45.1KB
Original post by itlstallion69
scatter graph is here

Well, the way that the Y values gravitate towards the X-axis tells you nothing about the X-Y relationship - rather it suggests that the distibution of Y is skew. I would suggest that you looks at the distribution of Y-values and see if it looks like anything you recognize; and then fit a smooth to the X-Y fit, to see what the X-Y relationship is like.
Original post by Gregorius
Well, the way that the Y values gravitate towards the X-axis tells you nothing about the X-Y relationship - rather it suggests that the distibution of Y is skew. I would suggest that you looks at the distribution of Y-values and see if it looks like anything you recognize; and then fit a smooth to the X-Y fit, to see what the X-Y relationship is like.

So a smooth curve looks like the linear graph y=2, but I`m not sure what this tells you about the variables, for example, does it imply any sort of relationship which is not linear, or can it tell us about the dependence of X on Y? Thanks
Original post by itlstallion69
So a smooth curve looks like the linear graph y=2, but I`m not sure what this tells you about the variables, for example, does it imply any sort of relationship which is not linear, or can it tell us about the dependence of X on Y? Thanks

Then that's telling you that Y is likely to be independent of X - i.e. no relationship between them.
The options kind of coincide though, (there appears to be some sort of relationship between X and Y but it is not linear// there is almost no dependence of X on Y).You`re saying there is no dependence and no relationship, which I agree with, but you can`t have neither (since the first option clearly isn`t true).
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mqb2766
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Original post by itlstallion69
The options kind of coincide though, (there appears to be some sort of relationship between X and Y but it is not linear// there is almost no dependence of X on Y).You`re saying there is no dependence and no relationship, which I agree with, but you can`t have neither (since the first option clearly isn`t true).


I'm not sure what you're concluding, but "there is no dependence and no relationship" appears correct. Nothing else.

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