Practical vs. Statistical Significance

[Guest guest]

At 10:30 AM 2/22/04 -0800, Juan wrote:

 

>I agree that in general statistics as used in science have proved of little

>use in astrology.

>

>Anny and Therese I'm surprised by your opinion here... Anyway....it may be

argued for the past as for the present and the future... that is(my

personal opinion) a different landscape..

>

>My question to you is simply how do you define Mars traits without Mars

present? Sure one can see some Pluto traits and mistake them for Mars but

hold 180 degreee difference of a opinion to the one you have expressed above.

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> [TH] However, the Gauquelins did a fine job of isolating traits for the

various

>planets. In the process they disproved some accepted meanings of planets.

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>Now I'm confused? Is the above more than " little use to astrologers " ?

 

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To answer all these questions it's necessary to have some understanding of

statistics and how they work. It's possible for something to be highly

significant via statistics, yet to have little practical value.

 

Suppose for example, that for a large statistical earthquake study, Uranus

was conjunct the MC 30 times more than chance would allow. This '30 times'

figure can actually be quite small compared to the total number of

earthquakes. This is why I don't accept Bradley's SVP research without a

lot of questions. Here's an article I found that describes practical vs.

statistical significance. It's really a very important article for

astrologers.

 

http://www.astrodatabank.com/AS/JoseBecerra.htm

 

No, Mars and Pluto traits are not at all alike according to Donald Bradley.

I agree with Bradley on that.

 

Therese

 

P.S. That article is tough going. Here's an excerpt:

 

" The measure of association most widely used – the one almost exclusively

used in most astrological research – is the Chi square test. It is usually

reported as a “p value” : the probability that the association found may be

due to chance. A low p value (inferior to 0.05) indicates that the

association found has less than 2 in 20 chances of being spurious.

Therefore, if we do an analysis of the house position of the Sun or of the

Moon in a sample (24 possible exposures), it is perfectly possible to find

a statistically significant p value that, with 24 exposures, is

nevertheless due to chance.

 

" A way around this problem of multiple comparisons is to find a p value

that is so low as to make irrelevant this objection. This was an important

part of the Gauquelins’ approach – in addition to a sound study design.

They have proven, for instance, a statistical association between the

position of Mars and Olympic champions. This approach, however, is

dependent on both the strength of the association and the sample size. A

p-value does not give us any information as to which of these two

components is mainly responsible for the statistical significance.

 

" What do I mean by “strength of association”?

 

" ***the Gauquelins found that, among sports champions, scientists, actors

and writers, 2,286 out of 8,737 (=26.2%) with typical sports champion’s

personality traits had Mars in the sectors following the horizon and the

meridian, whereas 20.4% was the theoretical frequency (see figure 1). The p

value for this finding is well below 0.000001, that is less than 1 in a

million, of being attributable to chance.***

(...)

" An astrologer counseling an individual with the Mars effect can tell

him/her that (s)he is approximately 0.4 times more likely to have sports

champion’s personality traits than others, a result of 1.0 being the

baseline of no special Marsian personality... "

 

(Excerpt from the ADB site: Practical Significance vs. Statistical

Significance in Astrological Research by Jose E. Becerra)