Articles, research notes and essays on predictive astrology, statistical methods and software.https://alexeyborealis.com/en-ushttps://alexeyborealis.com/blog/correlation/https://alexeyborealis.com/blog/correlation/Can statistical correlations prove astrology? Learn why p-values, effect sizes, and statistical power are not enough without a causal model and testable mechanism.Mon, 29 Jun 2026 09:30:05 GMThttps://alexeyborealis.com/blog/ml-code/https://alexeyborealis.com/blog/ml-code/Testing astrology using the scientific method: neural networks, data, and statistics. Implementing validation code from scratch in NumPy.Sat, 04 Apr 2026 19:35:56 GMThttps://alexeyborealis.com/blog/ml-astrology/https://alexeyborealis.com/blog/ml-astrology/Can astrological predictions be turned into a rigorous mathematical model? Learn how to train a computer to make predictions.Fri, 27 Mar 2026 08:14:43 GMThttps://alexeyborealis.com/blog/time-in-astrology/https://alexeyborealis.com/blog/time-in-astrology/Did you know astrology uses atomic time, cosmic clocks, and Earth’s rotation? Read how to use them for predictionsSun, 04 May 2025 04:09:48 GMThttps://alexeyborealis.com/blog/time-scales/https://alexeyborealis.com/blog/time-scales/Learn how UT, UTC, TT, and sidereal time influence astrological calculations. A simple explanation of complex concepts.Wed, 30 Apr 2025 16:06:49 GMThttps://alexeyborealis.com/blog/horary-astrology-study/https://alexeyborealis.com/blog/horary-astrology-study/Explore the pilot study comparing the accuracy of horary astrologers to random individuals in predicting event timings.Fri, 28 Jun 2024 11:08:58 GMThttps://alexeyborealis.com/blog/placidus-direction/https://alexeyborealis.com/blog/placidus-direction/A complete guide for astrologers: calculating a primary direction in Placidus house system with math formulas.Wed, 08 May 2024 09:42:52 GMThttps://alexeyborealis.com/blog/circle-of-aspects/https://alexeyborealis.com/blog/circle-of-aspects/Once it comes to primary directions, we need to observe the circle of aspects that doesn't coincide with the ecliptic.Wed, 08 May 2024 08:45:36 GMThttps://alexeyborealis.com/blog/placidus-mundane/https://alexeyborealis.com/blog/placidus-mundane/Equation of the mundane position of a planet from its right ascension and declination in Placidus house system.Wed, 08 May 2024 08:23:31 GMThttps://alexeyborealis.com/blog/placidus-cusps/https://alexeyborealis.com/blog/placidus-cusps/What is the mathematical equation for calculating the house cusps in the Placidus house system? For prof. astrologersWed, 08 May 2024 08:04:47 GMThttps://alexeyborealis.com/blog/ecliptic-equation/https://alexeyborealis.com/blog/ecliptic-equation/What are the correlations between right ascension, declination, and celestial latitude for any point on the ecliptic?Wed, 08 May 2024 07:27:37 GMThttps://alexeyborealis.com/blog/asc-mc/https://alexeyborealis.com/blog/asc-mc/Suppose you know the sidereal time and local coordinates. What is the ascending degree? The math formula for ASC.Wed, 08 May 2024 07:17:32 GMThttps://alexeyborealis.com/blog/ramc/https://alexeyborealis.com/blog/ramc/What is the right ascension of Medium Coeli, and how is it connected with sidereal time? Astrology knowledge base.Wed, 08 May 2024 06:32:35 GMThttps://alexeyborealis.com/blog/ascension-difference/https://alexeyborealis.com/blog/ascension-difference/A simple way to calculate ascension difference with use of spherical triangle equation. Astrological knowledge baseWed, 08 May 2024 06:19:14 GMThttps://alexeyborealis.com/blog/ecliptic-equator-conversion/https://alexeyborealis.com/blog/ecliptic-equator-conversion/What math equations are needed to express zodiacal longitude and latitude to the right ascension and declination?Tue, 07 May 2024 21:35:06 GMThttps://alexeyborealis.com/blog/spherical-triangles/https://alexeyborealis.com/blog/spherical-triangles/In this article, we derive math equations for spherical triangles, including the well-known theorem of sinuses.Tue, 07 May 2024 21:24:50 GMThttps://alexeyborealis.com/blog/rotation-matrix/https://alexeyborealis.com/blog/rotation-matrix/How to convert one spherical coordinate system to another? What are the rotation matrices, and how to use them?Tue, 07 May 2024 21:10:24 GMThttps://alexeyborealis.com/blog/basic-trigonometry/https://alexeyborealis.com/blog/basic-trigonometry/What do sine and cosine mean, where do they come from, and how are coordinates of the celestial point relate to themTue, 07 May 2024 20:55:25 GMThttps://alexeyborealis.com/blog/regiomontanus-basics/https://alexeyborealis.com/blog/regiomontanus-basics/What is the circle of position, mundane position, and conjunction with the cusp in the Regiomontanus house system?Tue, 07 May 2024 20:36:13 GMThttps://alexeyborealis.com/blog/placidus-basics/https://alexeyborealis.com/blog/placidus-basics/What is the curve of planetary position, mundane position, and conjunction with the cusp in the Placidus house system?Tue, 07 May 2024 20:33:36 GMT