Luis A. Mateos

The golden grail for computer predictive systems in the stock markets is to predict accurately when to buy and when to sell assets, regardless of the unexpected ups and downs on the markets.

However, predicting the stock markets has been hard and perhaps it is an impossible task. There are so many elements and circumstances involved in the outcome of stock prices, such as: global/local political, the pandemic (COVID-19), economical and environmental factors to mention a few. In addition, the individual investors add an extra factor to the common trends in the market. These individual investors may base their decisions on news, fake news, the place they worked, gossip from friends, the mood they were on that day, etc.; without making any rigorous analysis of the markets.

Even if some financial institutions use strategic mathematical methods which incorporate most of the factors affecting the stock markets and can predict the trend of the markets in some way. The individual investor behavior can affect the predicted trend unexpectedly. Nowadays, anybody with a cellphone and a market app can play (invest) in the stock markets and alter the market unexpectedly. One recent example was the exponential increase in the Game Stop - GME stock in early 2021, followed by AMC hike.

Thus, there will not be an accurate predictive system (with or without AI) for stock markets until it can understand all the variables and factors affecting each of the investors and their reason for buying and selling stocks.

oon Phases

There are four major "lunar" or Moon phases: New Moon, First quarter, Full Moon and Third or Last quarter.

New Moon. This is the invisible phase of the Moon, with the illuminated side of the Moon facing the Sun and the night side facing Earth. In the new moon or full Moon, the tide's range is at its maximum.

First quarter. The Moon is now a quarter of the way through its monthly journey and you see half of its illuminated side.

Full Moon. This is as close as we come to seeing the Sun’s illumination of the entire day side of the Moon. The Moon is opposite the Sun, as viewed from Earth, revealing the Moon’s dayside.

Third (Last) quarter. The Moon looks like it’s half illuminated from the perspective of Earth, but really you’re seeing half of the half of the Moon that’s illuminated by the Sun.

Four major Moon phases (right). Irregular periods from the Moon phases (left).

These phases are not consistent in time with respect to the Solar calendar. Since, one phase on a given month may consists of 7 days and in the next month of 8 days. In the same way, a given Moon phase will appear in different day of the month. For example, the full moon for the month of May in 2021 was the Wednesday 26th of May, whereas for the next month was the Thursday 24th of June.

The Moon affects the earth in a physical way. One example is the tide, which is at it's maximum in the new moon or full moon. In the same way, the moon affects human, either from the light at night or from the gravitational pull making us sleep more or less minutes and affect the behavior.


In Shakespeare’s “Othello,” the maid Emilia tells Othello that the Moon has drawn too close to the Earth — and driven men insane.

As far back as 400 B.C., physicians and philosophers blamed behavioral changes on the pull of the Moon. The word “lunatic,” after all, came from the idea that changes in mental state were related to lunar cycles.

The connection between the two is even supported in historic legal treatises: Famed British jurist William Blackstone wrote that people gained and lost their ability to reason according to the Moon’s shifting phases.

How the Moon may affect humans

One recent study suggested that outdoor criminal activity may be higher when there is more moonlight [].

In theory, the light of a full Moon might disrupt people’s sleep, which could influence their mood [].

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Here, I just want to comment a few things about the Moon affect on humans as introduction. In the next section we focus on the numbers in the stock market mapped to the lunar phases together with common time sampling variables.

2021 Luis A. Mateos