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Five Starting Points 
for statistical studies 
in astrology
Kyösti Tarvainen
PhD, Docent in Systems Analysis
Oct. 9, 2015

Dr. Kyosti Tarvainen has obtained some highly significant results in recent years, many of which have been regularly peer-reviewed & published in Correlation 
 Dr. Tarvainen wrote the following essay especially for the Kepler Conference participants. We want to strongly encourage researchers to learn from his methods, and try to replicate and expand upon these important results. 

This is a report on my five starting points for astrological studies. The positive results I have obtained have given not only ample support for modern psychological astrology, but also some answers to technical questions related to zodiacs, house systems, orb sizes, etc.

I started to do large-scale astrological studies in 2006, after obtaining part-time retirement from mathematics teaching. Fortunately at that time, the Gauquelins’ data was available on the Internet. I am very thankful to the Gauquelins, since without their data, I could not have started the studies and obtained most of my results. 

Another fortunate thing in 2006 was that the calculating power of personal computers had increased so much that extensive control group generations and various simulations were possible. 

The following five starting points (SP) have guided the research:

  • SP 1 (multiple factors). Since there are so many astrological and non-astrological factors, it is difficult to obtain statistically significant results for single factors. Therefore, generally the overall significance for several factors has to be considered.


This approach is consistent with the fact that many astrology books state that there must be more than one factor pointing in the same direction for a trait to manifest prominently.

Undoubtedly the most important reason why Michael Gauquelin did not find support for ordinary astrology in his data was that he studied the effects of single factors. This single-factor approach was natural, due to the limited computing possibilities of his time.  In fact, he actually started with hand calculations.


But with today’s computing power, by taking into account multiple factors, we see in references 1,2,3,4,5,6,10,11,13 below that the Gauquelins’ data gives plentiful confirmation to ordinary astrology.


  • SP 2 (psychological astrology). Astrology has made great progress, starting with Alan Leo, using a psychological approach. The main interest has been in person-centered, psychological astrology. 
Therefore, I thought it best to concentrate on this well- established form of modern, natal astrology.


Naturally all branches of astrology can be studied, but the most convincing confirmations of the validity of astrological statements have been obtained in natal astrology.  

  • SP 3 (prominent astrologers). I have found it best to study the sayings of prominent psychological astrologers and their techniques (instead of just “fishing”). It is accordingly appropriate to set up research hypotheses at the beginning of the research, not after. 


The sayings of prominent astrologers usually relate to common, central issues so there is a bigger probability that these sayings can be verified by statistical studies, rather than those related to more rare issues, where a small astrological effect may be present but its detection demands more data than is available. 

Results obtained by fishing, or data mining, should at least be verified in another separate set of data, but often this is not possible due to a scarcity of reliable, accurate data.  Further, since there are so many astrological factors, one factor may show up prominently just by chance in fishing, whereby an actual, working factor may seem less prominent.


  • SP 4 (person-centered astrology).  Morin stated as early as the 17th century that the astrological chart concerns the person him/herself. Therefore, I found it best to study those things that depend on the persons’ behavior (not, for example, accidents or events that depend on others).


For example, a negative result was obtained in a study made by The Finnish Astrological Association, which tested whether the deaths of a person’s relatives were reflected in the transits, progressions or solar arcs in the person’s birth chart. Their results were only at chance expectancy.


  • SP 5 (scientific thinking). I believe that there is some physical mechanism behind the astrology (for example, the astrological factors at birth may slightly modify the workings of genes). Therefore, we might expect that abstract, or mathematically complicated astrological methods would not work in nature. 


For example, one such mathematically complicated method which seems difficult for nature to carry out is the Trutine of Hermes. In [12], we were able to obtain statistical confirmation for the old opinion that it doesn’t work.

A:  Positive Results Obtained
The following positive results have been obtained using the above starting points:
  •  In order to test SP 1 (multiple factors), I used Henning’s potentials which combine several astrological factors. The study [1] gave support for the validity of ordinary astrology in the Gauquelins’ professional data, containing over 18 000 persons.

  • In [2], several factors were taken into account by testing how many of 316 statements in the handbook of Sakoian and Acker are valid in the Gauquelins’ professional data containing over 18 000 persons. Statistical significance was obtained, and factors related to signs, houses and aspects did work.
  • Also in the synastry study [3], several factors were considered. In addition to the aspects between spouses’ Suns, also aspects between other “favorable” or “neutral” points where taken into account (SO, MO, ME, VE, JU, ASC and MC were considered). Inter-chart aspects obtained statistical significance. Very clear significance was also obtained when considering the houses in which the partner’s Sun falls. The Gauquelins’ heredity data, containing over 20 000 marriages, was used.
  • In a study concerning VE/SA aspects [4], all major aspects were taken into account. Statistically significant results were obtained for the age difference by husbands and the delay of marriage by husbands and wives. The Gauquelins’ heredity data, containing over 20 000 marriages, was used.
  • In a study concerning forecasting methods [5], I examined the birth charts of parents during the months before the estimated conception of their child. Using the Gauquelins' hereditary data, containing over 20,000 fathers and 20,000 mothers, I found that transits and solar arcs (Naibod) produced the most significant correlations.

  • In the Gauquelins’ professional data, containing over 18,000 persons, the chart Ruler (the planetary ruler of the Ascendant sign) was situated significantly often in a house traditionally related to the vocational group the person belongs to [6]. This study is, thus, a confirmation of the relationship between signs and their ruling planets and a verification of the importance of the chart Ruler’s house. Indirectly, the study also gives some verification of the existence of astrological signs.
  • To study mathematicians, the birth dates of 2,759 mathematicians were collected (not including the birth hour). Overall statistical significance was observed for favorable factors mentioned by Sakoian and Acker [7].
  • The birth dates of 6,285 theologians were collected (not including the birth hour). Favorable aspects mentioned by Robert Pelletier in his aspect book obtained overall significance. Also minor aspects obtained overall statistical significance [8]. Some of the minor aspects were proposed by Kepler.
  • Synastry statements concerning conjunctions to partner’s lunar Node obtained confirmation in [11]. In this study, we encountered a rare case when verification for a single favorable factor could be obtained: the Sun conjuncting the partner’s North Node. The Gauquelins’ heredity data containing over 20,000 fathers and 20,000 mothers was used.

B. Negative results

I could not obtain the anticipated positive results in only one large-scale study.  Robert Pelletier gives 44 aspects favorable for lawyers. But among the collected 17,767 Finnish lawyers, the aspects did not have overall significance (p=0.27).  In fact, among them, there were 318 doctors with a smaller p-value 0.06. 
Pelletier seems to have misidentified the 44 factors.

In fact, it is difficult to specify common astrological factors for lawyers, since there are many different professions for lawyers and, in principle, almost everybody can become a lawyer (this is not the case with mathematicians or theologians). A common feature for lawyers is that their work is very mental like the profession of journalists. In fact, if we consider 15 sign and aspect factors that Sakoian and Acker state favorable for journalists (factors related to Gemini and Mercury, see [2, p. 18]), they have overall statistical significance among the collected lawyers (p=0.02).

At the same time, some of the other negative results obtained were almost hoped for, or no surprise, considering the starting points SP 1-5. In addition to the Hermes study mentioned above, and the relatives’ death study, other such negative results include the following:

  • When studying Jonas’ theory in [9], no support was found for his claim that a baby’s sex is determined at  conception, which would be somewhat suspicious according to SP 5 (scientific thinking). Regarding Jonas’ other claim, there were, indeed, relatively more conceptions at times when the mother’s Moon phase was the same as that at her birth, but this doesn’t yet prove that there are two fertility cycles, as Jonas claimed. It may be that, for this group of women, the fertility and Moon cycles are synchronized, which as such is an interesting thing and worthy of further study.

  • In the synastry study [3], Davison’s method and the composite chart method did not work. If we think that the astrological positions are somehow imprinted at birth to the person, a natural mechanism that would do the mathematical calculations of these two methods seem very complicated for nature (SP 5, scientific thinking).

  • In the forecast study [5], the day/year progression method did not obtain support. Also some astrologers have doubted this method. It includes the problematic thing that it seems like the body should store the movements of planets during about hundred days after the birth. Kepler considered only the Sun and Moon in this prediction method. These planets move at a rather constant speed and, hence, we do not have the same “ephemeris problem” as with other planets. But naturally more studies are needed. 

C. Technical Results for Astrology

Since several working astrological effects were observed, they could be used to study technical matters of astrology:

  • In the chart ruler study [6], clear statistical confirmation was obtained for the fact that the tropical zodiac works, but the sidereal one doesn’t.


  • In the chart Ruler study [6], it was seen that also the old Rulers (Mars for Scorpio, Saturn for Aquarius and Jupiter for Pisces) worked as chart Rulers (in addition to the new, slowly moving ones). It was noticed that, in addition to the house where the Ruler is situated, also a house containing its Ruler (the Ruler of the cusp sign) is especially strong.


  • In [3] and[6], a house system comparison could be made. In both cases, the Koch houses worked best. Also in a study made in The Finnish Astrological Society, Koch worked better than Placidus (see [1, footnote 9]).


  • Minor aspects were surprisingly strong in theologians’ charts [8]. The orbs (for other than inconjuncts) seemed to be somewhat smaller (1°-1.5°) than often presented (about 2° in several books).


  • For major aspects, orbs could be estimated in five studies. In the VE/SA study [4], a common orb for all Ptolemaic aspects (including 60°) was estimated to be 5°-7°.  In theologians’ charts [8], a common orb for 0°, 90°, 120° and 180° aspects seems to be 9°.   For mathematicians [7],  a common orb of 8° was determined for 0°, 90°, 120° and 180° aspects.  These results give confirmation to the natal orb sizes the modern astrology books usually recommend (not to the small orb of 5° that Robert Hand recommends in his renowned book Horoscope Symbols). Concerning synastry orbs, in [3], a common orb for conjunctions and trines between the charts was estimated to be 9°-12° plus 2° for SO, MO and AS. In the Node synastry study [11], an orb of about 10° was observed for Node conjunctions. The synastry orb observations are interesting since opinions concerning these orbs differ widely in the astrological literature.  An interesting preliminary observation concerning natal charts is made in [13]: wide aspects seemed to be about as strong as tight ones.

Hence, statistical studies not only confirm that there are astrological effects (although tiny, since big amounts of data are needed), but we see that statistical studies are also useful when studying technical matters of astrology.


The relatively large sizes of the data samples have proven essential to these successes, especially since it seems that many astrological studies have fallen through with smaller sets of data. Big data sets are necessary, since there are hundreds of astrological and non-astrological factors. In the fore-mentioned studies, there was one very special sub-case where only 100 birth charts were enough to obtain statistically significant results: the most prominent mathematicians who have received a Noble-like prize.


In all studies, control groups were used. In most cases, the control groups were computer generated by shuffling, and their validity is verified by simulations in [2].


As mentioned above, my large-scale studies started with the Gauquelins’ timed charts. But I have then noticed in [7] and [8] that, in aspect studies, it is possible to obtain positive result also for untimed charts. The reason being that many aspects last for several days, and, for such long lasting aspects, the use of noontime gives results which are usually accurate enough. If needed, a simple simulation procedure can be used to study the accuracy [13]. In aspect studies, more positive results can be expected.  In fact, Kepler himself stated that aspects are the strongest astrological factors.

After posting the article above on Facebook, on Oct. 27, 2015, Paulo Mendes (see the sidebar on the right) raised a number of questions about Dr. Tarvainen's statistics - without even reading the articles cited.  

Kyosti's reply, which reveals even more about his methods, is posted below. 

Please, before tearing into someone's work and dismissing it in a public forum, 
at least have the courtesy to actually read it first. 

Kyosti Tarvainen
Paulo, if I had tested several hundred hypotheses and found that about ten obtain confirmation, I would have reported on this with the conclusion that there seems to be no truth in astrology.
But I have not tested several hundred hypotheses. I have earlier made about five astrological studies using small sets of data in our local astrological society. Then in 2006, I started to do large- scale studies using the Gauquelins’ data. I have also collected birth dates of all Finnish theologians and lawyers, all mathematicians in a control-science magazine, all about 2000 prominent mathematicians (born after 1700) in a biographical collection. I have always used all data, not only subsets.

According to one of my starting points, I have studied the sayings of prominent astrologers. Thus, I have not experimented with different combinations of astrological factors or with my own hypotheses.
I have not experimented with different orb sizes. As a starting point for each study, I have used the orb sizes prominent astrologers have recommended. Then, I have been later studied what the real maximum orb seems to be in the data. These observed, estimated orbs have not differentiated much from those astrologers have recommended. The only different situation was in the Moon’s Node study, since the recommendations for orbs in synastry vary much in astrological literature. Therefore, I used a similar method that Mike O‘Neill used in his Node study to determine the working maximum orb, ending up with the synastry orb of about 10 degrees.
I have not needed to use Bonferroni correction since, according to one of my starting points, I have considered the overall significance of several factors. For example, in the case of mathematicians, I did not study the statistical significance of every single factor Sakoian and Acker see favorable for mathematicians. Instead, in effect, I considered the average number of these favorable factors each mathematician has. The main reason I have obtained positive results is just the fact that I have not considered single factors, but overall significance of several factors that point in the same direction.

In summary, I have made about ten large-scale studies. For each case, based on the saying of prominent astrologers or generally accepted astrological knowledge, one, or a couple of hypotheses due to different considered methods, has been set up. In only one case where I would have expected a positive result, sayings of a prominent astrologer did not obtain confirmation (Pelletier’s favorable aspects for lawyers – somebody could still study if they are valid for American lawyers who at least in movies are different from those in Europe).
I am convinced by experience that there are astrological effects. Therefore, I am not surprised that one can get positive statistical results. But I am surprised that my own studies have overwhelmingly produced positive results. Perhaps I have had luck in selecting the research themes, but certainly the main secret for success has been the five starting points, especially the first one (multiple factors). 

In any case, you should notice that confirmation has been obtained to the sayings of prominent astrologers in three major themes in present astrology: 1) natal astrology, 2) synastry (classical synastry), 3) prediction methods (transits, solar arcs).

For skeptics, astrology is speculation. Thus aspect orbs are like speculations around speculations. How could one then explain that the orbs the computer has mechanically estimated are close to those astrologers have recommended. You should notice that these orb estimation results are thus also remarkable.
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