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Re: OK – I think I’m set, at least till we get t o c on (e, u, u*e).
Posted:
Nov 28, 2012 5:59 PM


On Nov 27, 6:19 am, djh <halitsk...@att.net> wrote: > [...] > > 4. > > Apart from correcting the general theoretical deficiency which you > perceive as arising from uL/uH dichotomization itself, another benefit > of doing the reanalysis with the three new regressions is presumably > that it will help us improve the two tables I presented at the end of > the other thread: > > Table I: > > Extent to which Significant 3way Interactions > across Length Intervals > are Exhibited at Specific Length Intervals > (Data Not Shown for 2RS and 2RC) > > 3way u NonRandom > Coeff Len Int p Lev 2S 2C % Chg > eS ALL .014 L 2.288 6.075 165.5% > H 7.993 8.309 4.0% > > 1 .035 L 1.578 6.545 314.6% > H 5.719 4.760 16.8% > > euSe ALL .005 L 2.402 6.154 156.2% > H 8.265 7.975 3.5% > > 1 .025 L 2.076 6.640 219.8% > H 6.002 3.926 34.6% > > 4 .011 L 1.250 7.881 530.3% > H 10.755 7.658 28.8% > > uS ALL .0003 L 0.277 0.082 129.6% > H 0.050 0.848 1796.0% > > 5 .040 L 0.287 0.345 20.0% > H 0.289 0.325 212.3% > > 9 .0002 L 0.548 0.078 114.2% > H 0.436 1.056 342.4% > > 10 .011 L 0.563 0.006 101.0% > H 0.261 1.103 522.9% > > 11 .032 L 0.617 0.142 123.1% > H 0.354 1.178 432.9% > > euSu ALL .036 L 0.240 0.037 115.4% > H 0.190 0.760 300.0% > > 9 .008 L 0.482 0.067 113.8% > H 0.141 0.829 686.3% > > 11 .012 L 0.415 0.083 120.1% > H 0.185 1.253 777.3% > > Table II: > > Bonferroni Correction of p?s in Table I > > TstVal= > .025/ p(j) > j Category p(j) (14j) TstVal > > 1 uS9 .0002 .00192 .00177 > 2 uSALL .0003 .00208 .00178 > 3 euSeALL .005 .00227 .00264 > 4 euSu9 .008 .00250 .00559 > 5 uS10 .011 .00278 .00779 > 6 euSe4 .011 .00313 .00784 > 7 euSu11 .012 .00357 .00819 > 8 eSALL .014 .00417 .01032 > 9 euSe1 .025 .00500 .02016 > 10 uS11 .032 .00625 .02528 > 11 eS1 .035 .00833 .02701 > 12 euSuALL .036 .01250 .02366 > 13 uS5 .040 .02500 .01523 > > In particular: > > (A) with respect to the equivalent of Table I that will be constructed > from the new 2ways, I am hoping first that more of the new 2ways at > specific lengthintervals will show probabilities < .05, as opposed to > the paltry yield of ?good? intervalspecific 3ways in the current > table. > > (B) with respect to the equivalent of Table II that will be > constructed from the p?s in the new Table I, I am hoping that more of > these p?s (both crossinterval and intervalspecific) will withstand > plausible Bonferroni correction. > > Is there any reason to assume A PRIORI that (AB) will not be the > case, due to some subtle theoretical reason that I?m too ignorant to > see? And more generally, is there a better pair of tables that should > be generated for the new 2ways, instead of tables like (III): > > Also, just out of curiousity, I?m wondering if it would be legitimate > to ?allow? row 3 in Table II as well as rows 1 and 2? (You mentioned > once that some manual tinkering with Bonferroni results is allowable.) > > Thanks as always for your considered consideration of these matters. > It will take me 23 days to add code and rerun for c on (u,u^2) with > computation of a firstcut ?average? slope, depending on dayjob > demands. > > In the meantime, I?m hoping you?ll continue your exegesis with an > explication of c on (e, u, u*e), the second of the three new > regressions.
re Table I: "% Chg" (percent change?) is not a good measure here. The analysis itself looks at the simple differences. Percent change, (or its alternate form, relative difference) is rarely appropriate when the two values involved can have different signs.
re Table II: The trick is to compare p(j)*(14j) to alpha, instead of comparing p(j) to alpha/(14j). That way you can simply scan down and see what you would have to change your chosen alpha to in order to declare the j'th test "significant". Thus, .005 * (143) = .055, which is twice your chosen alpha (.025) and so should probably not be called significant.
Also: why .025 instead of .05? Are the p's onetailed when you really want them to be twotailed? Such things should be part of the report.



