Some people claim to be able to predict minute details of our lives based on the positions of the planets at the times of our births; this is the practice of astrology. Every so often a piece of pseudo scientific bunk comes and gets right under my nostrils and wafts itself just long enough to cause my eyes to water. This results in me ranting to Bob (who sits next to me in the office) until he tells me that I should actually write something about such foolishness...this is the result.
I went online and downloaded 15 horoscopes for me (a Cancer if you must know) that makes some predictions about my emotional or physical state today (June 09, 2011). Now 15 isn’t a massive sample size, but more than enough for the tests that I am planning to do on the data. If I really wanted to prove this I would collect a few more horoscopes (to the critics out there).
Now from these datasets individuals were asked to rate how positive the predictions or assessments were. A score of 1 meant it was a bad day, hopelessness and despair reign; apparently I would be best just staying at home hiding from the world. A score of 5 meant that I have a brilliant day to look forward to; bunnies, rainbows (with pots of gold), romantic success and work brilliance. So now we have an index of how well each horoscope felt I would do on this one particular day. All horoscopes were constructed using the same system of Western Sun sign astrology (no Chinese zodiacs creeping in here, although it didn’t stop one from mentioning Ganeesha who is not responsible for any zodiac system) so should as such make similar predictions for my day. Well here are the results:
Not many 1’s but a pretty even mix of all of the other values. Is it different to a random selection of scores? I simulated 100 datasets of 15 values 1:5 using a uniform distribution, i.e. any one of the values were equally likely. I then compared these simulated (and totally random between 1:5) values with our list from a horoscope. The result was, no significant difference in the mean scores between these samples (p-value = 0.6, mean of the horoscopes= 3.4, mean of the randoms= 3.51). So there is basically no difference between making up a score for the horoscopes and the relative predictions they make.
At this point someone could jump in and say, ‘Well Mark! Horoscopes may well differ in how they present the information, but the core message is conserved.’ This could indeed lead to different emotional scores and yet have the same key message underneath it all. I also did a keyword analysis to debunk this. Keywords (such as fear, hate, success, opportunity, love, magnetism etc) were only repeated in two of the horoscopes. With fuzzy matching (happiness is the same as joy, hate the same as anger etc) this number only rose to 4. Indeed results ranged from predicting a monetary windfall from an aging relative to romantic success, accelerated mental processes (awesome!), oozing charm and all the way to serious emotional disturbances.
Four of the entries were directly contradictory, noisy and disturbed thoughts and difficulty concentrating was the exact opposite to sudden insights and enhanced mental processes. Equally brilliance at work was predicted by one website followed by patience and persistence required with a project going nowhere by another.
I say, go out and check for yourself, consistent records between individual horoscopes have shown time and time again that they are not consistent. If there was a genuine casual mechanism responsible for changes here on earth relating to planetary position, it would be measurable and testable. There could well be a mechanism by which gravity of foreign bodies affects our behaviour; it’s not beyond the realm of logic. The sun and moon do have measureable effects on human happiness, with suicide being directly related to day length (sorry Sweden). I am simply showing that current astrology does not hold to a meaningful method (it is not consistent) and fails to make testable predictions.