## Posts Tagged ‘**logarithms**’

## algorithms, logarithms and biorhythms

In a recent conversation I was talking about the algorithms used by organisations like Facebook and Google to get people hooked into reading or listening to or otherwise attending to a whole host of stuff related to what they attended to yesterday. My interlocutor continued the conversation, but inadvertantly replaced the word ‘algorithm’ with ‘logarithm’ throughout, which I didn’t correct, perhaps not so much out of politeness but because, though I knew enough about the difference to use the right word, I would have difficulty in defining either term, in case he asked. As for biorhythms, I threw them in just for fun.

Mathematics is probably my weakest subject, and for that reason I’ve often been drawn to it in my dilettantish fashion, as to a kind of secret society I’ve been excluded from due to lack of the requisite. So I’ll start with my extremely limited and probably wrong working understanding of algos and logos (and bios), then provide a more informed account through a bit of research.

An *algorithm*, I think, is a largely computer-generated aggregate of a person’s data-gathering which provides some predictive power about their future data-gathering, or future interest, so that the data can be presented to them for gathering. Or something like that. A *logarithm, *I think, has something to do with exponentials. So that if something increases exponentially, it also increases logarithmically. Or logarithmickly? Or maybe a logarithm is some mathematical relation between a number and its exponent. Or something like that. A *biorhythm *is something to do with your supposed natural cycle of activity/inactivity throughout the day. It was new age stuff of the seventies, my early teen years. It seems to have died the death.

So now for the details and correctives.

An algorithm is indeed most associated with computing and data processing, though it may be used in a broader sense, mathematically or not. In fact it can be used to describe the *process *to get any result. In that sense a cookbook is a set of algorithms. But even in computing, the term is broader than my working understanding of it implied. I was thinking of *particular *algorithms, the ones used by certain web presences like Google, Facebook and Netflix to get you hooked into continuing to use them. To get you addicted, in a sense. So that’s all that needs to be said here about algorithms in general. In another post I’ll look at those particular algorithms that have worked so well for their creators (or the hirers of those creators) that they’ve become some of the richest folk in the world. That should be much more interesting.

A logarithm is also something like what I thought it was, but of course my understanding was very vague. It’s described as the inverse function to exponentiation – just as I sort of thought. For example, take the number 64, and think of it as 2 x 2 x 2 x 2 x 2 x 2, or 2^{6 }. The 6 here is the exponent (*n*), while the 2 is the base (*b*), so the general formulation is *b*^{n}. The exponent (*n*) is also called the *power*, as in two to the sixth power, 2^{6}. Now, say that you want to know what power to raise the number two to get 256. That’s to say, 2^{n} = 256, find *n*. This number that we want to find is the logarithm. So the question or equation can be restated thus:

log2(256) = *n* , find *n*

and the answer is *n *= 8. So the logarithm is the *power* that we have to raise a specified (base) number to, in order to get to another specified number. That’s all we need to know as a beginning. Obviously it gets more complicated with higher powers – but then, with higher powers, anything’s possible.

A biorhythm chart is a development of ideas concocted by one Wilhelm Fliess, a good mate of the only slightly less eccentric Sigmund Freud, back in the late 19th century. I well remember this fad gaining super-popularity in the seventies, with a paperback on the topic floating around our household. That and ‘speed reading’ were all the go. The basic hypothesis was that our lives – presumably in terms of energy, ‘clarity’ and competence – go in cycles, which can be charted as sinusoidal waves. The standard model argued for a 23-day physical cycle, a 28-day emotional cycle and a 33-day intellectual cycle. I’ve actually met someone who drew up these charts for herself back in the day. You live and learn. Needless to say, there’s no evidence whatever to back these ideas up, but they’re claimed often as ancient learning which has been eclipsed by the monstrous juggernaut of modern science, much like that other font of cyclical predictive wisdom, astrology…..

**References**

https://computer.howstuffworks.com/what-is-a-computer-algorithm.htm

Khan academy video: intro to logarithms