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I performed a regression analysis with two datasets, each of which has size `50`

. One dataset is called `Spatial %`

and the other `Min values`

, and I wanted to check whether the two are correlated. I did the analysis in `SPSS`

and the resulting scatterplot is as follows:

I am not that much experienced but it seems to me that a line is not the perfect fit for this scatterplot. Would a power line fit better? Or what else do you suggest?

1Did any of the existing answers helped you solve the question? If yes, then please mark it as accepted :) – Dawny33 – 2015-11-19T17:45:29.793

You say "two different datasets" but then plot them as if they are one dataset with two features. Is that what you really want? Also, you say "want to find the correlation", but then never check the linear correlation, do you want to check the linear correlation before moving to nonlinear? Though it might not "look" like a line is a good fit, there are plenty of cases where points get stacked on top of one another so the distro is linear and its only the outliers that are nonlinear. Lots of posters seem to be jumping to nonlinear without fully vetting linear. I advise being disciplined. – AN6U5 – 2015-11-19T20:39:33.353

The dots you see have their x values coming from one dataset and the y values coming from another. How would you check if there is a regression line that could be fit, if you don't plot them this way? – FaCoffee – 2015-11-20T08:56:04.910

As for the linear correlation: I failed to imagine how a linear regression could even fit this scatterplot. Look at its shape: it suggests some exponential curve fits them best. This is also confirmed by the two answers that I got. You are right, there could be a partial linear regression which may serve the cause, but look at those that would become outliers: aren't they too many to "get rid" of them? – FaCoffee – 2015-11-20T08:58:02.487

I have tried to export the graph values, with limited success. Could you please share the data? – Laurent Duval – 2015-11-29T08:32:00.860