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Findings from Figure 2

Posted by profandyfield on 02 Apr 2013 at 17:20 GMT

The correlation reported for Figure 2 (-.79) is probably an overestimate resulting from the first and last case in the data. Using this figure to estimate the raw data you get an r as low as -.37 using some robust methods, and if you bootstrap the confidence interval around r, it is very wide (-1 to about 0.6) implying that the population effect might be very different to that reported. I elaborate on these computations at http://discoveringstatist...

Of course the presence of two data points that might be affecting the r from Figure 2 is interesting in itself - it would be interesting to know what it is that made these cases different to the main cloud of data.

No competing interests declared.

RE: Findings from Figure 2

mailbox_gm replied to profandyfield on 03 Apr 2013 at 09:10 GMT

Thank you. Based on your suggestions we will work on it, and come back to you as early as possible.

No competing interests declared.