On local oldies radio heard Jimi Hendrix playing his masterpiece, All Along the Watchtower, the other day. Dylan wrote the song 1967 or so, and Hendrix recorded it 1968. I recall at the time being mesmerized by completely unique electric guitar riffs and audio processing, Hendrix more or less creating the acid rock style that was soon taken up by other players for decades. The lyrics were another nod by Dylan to the Old Testament apparently, he probably being familiar with those verses (like many of us of past years, the words of the Bible are an eloquent underpinning to much of our thought, form and substance). Isaiah Chapter 21, verses 5–9 (KJV):
21:5-9 Prepare the table, watch in the watchtower, eat, drink: arise, ye princes... For thus hath the LORD said unto me, Go, set a watchman, let him declare what he seeth. And he saw a chariot with a couple of horsemen... and he hearkened diligently with much heed: And he cried, A lion: My lord, I stand continually upon the watchtower in the daytime, and I am set in my ward whole nights: And, behold, here cometh a chariot of men, with a couple of horsemen
I actually had tears in my eyes when I heard of Elizabeth II's passing and watched some of the many retrospectives on her. For me, aging and despairing at the course of humankind, it was more than simply the death of a good-hearted queen, monarch of a country which I still feel a great affinity for (as many of the original colonists and their kin). It was yet another loss of a type of nobility and integrity that is vanishing now. I mourn the death of both. It was telling to hear American news folks somewhat puzzled at the quiet reverence of thousands of Brits who gathered to see her off---the type of people who left Britain for the New World were definitely not the type who remained!
I watched a PBS special on the 1930's Dust Bowl climate disaster recently. I was fascinated with the reaction of the inhabitants of the Oklahoma/Texas areas affected, the denial and attempts to persist in their previous habits and life:
This is of course highly relevant as I watch a global catastrophe occuring now, almost weekly damage and disruption of America from wildfires and vicious weather (well said by California governor Newsom to be "nature's fury"), flooding, destructive winds, rising sea levels inundating coastal areas, roasting humanity with unheard-of heat. A core of Americans react this time with the same denial, but with the added viciousness of the child of poor character encountering limits. And still we have the counterbalance of the perverse academia-media axis who "Who feel that life is but a joke" (from All Along the Watchtower). Four horsemen are approaching, and the wind indeed has begun to howl!
I have spent recent weeks studying combinatorics, the related topic of permutation testing in statistics being as chaotic and imprecise as mud-wrassling a greased-hyper-pig, as we used to say in my hippie-dog days late 60's southwest Texas (well, as I would have said if I had been devoting much time to the problem then). Permutation is the process of producing new orderings of a sequence, think of quickly switching the order of three cups under which one hides a treat while trying to test your dog's intelligence (if that is still permitted, after all, the dog has its own cultural traditions).
I ran a simulation of the random reordering of the differences in height of Zea mays plants grown by Darwin to test the superiority of cross-bred over self-fertilized (I have mixed feelings about the relative merits of both at this point in history, but that is another matter). This was suggested by Ronald Fisher in his 1935 Design of Experiments, thus initiating the subject of permutation testing, though, to my continuing irritation, subsequent practitioners tossed precise usage of mathematical terms out the window and loosely referred to any shuffling of data and labels as "permutations."
The idea is that if you have a true experimental effect, in this context that a cross-bred plant will grow a bit higher (and attain a higher standard of living?) than its poor self-fertilized competitor, if you randomly change the signs (plus or minus) on the measured differences in height and count how many times the sum of the differences (one way to do it; there are other test statistics possible) is as extreme as that originally observed, then you can estimate the probability that you are seeing a random effect rather than a true experimental result. On the following plot I mark the observed original statistic with a vertical red line. The blue histogram plots the count frequency of randomly shuffled sums (sums of randomly alternated signed height differences), most being much lower, suggesting that our observation is unlikely to occur by chance:
The good Christian should beware of mathematicians and all those who make empty prophecies. The danger already exists that mathematicians have made a covenant with the devil to darken the spirit and confine man in the bonds of Hell.
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