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Or you could just toss a coin for each patient.If you are concerned that your coin may be balanced, toss it twice.If you get HH or TT toss twice more (repeatedly if needs be).If you get HT then assign them to the placebo group, if you get TH assign them to the treatment group.

Quote from: Bored chemist on 03/07/2021 18:41:06Or you could just toss a coin for each patient.If you are concerned that your coin may be balanced, toss it twice.If you get HH or TT toss twice more (repeatedly if needs be).If you get HT then assign them to the placebo group, if you get TH assign them to the treatment group.If the first coin is biased towards head, or the second coin is biased towards tail, then the patient is more likely to get placebo, and vice versa.

as far as I am concerned a set of 2-digit integers generated by Excel RAND is indeed adequately random, but you still need to filter out duplicates.

but it's easy with a random number table because one third will be divisible by 3, one third by 2 but not 3, and one third not divisible by 2 or 3.

Quote from: hamdani yusuf on 03/07/2021 22:40:02Quote from: Bored chemist on 03/07/2021 18:41:06Or you could just toss a coin for each patient.If you are concerned that your coin may be balanced, toss it twice.If you get HH or TT toss twice more (repeatedly if needs be).If you get HT then assign them to the placebo group, if you get TH assign them to the treatment group.If the first coin is biased towards head, or the second coin is biased towards tail, then the patient is more likely to get placebo, and vice versa. Did you notice that I said "coin" not "coins"?It's not me you are arguing with"John von Neumann invented a simple algorithm to fix simple bias and reduce correlation. It considers two bits at a time (non-overlapping), taking one of three actions: when two successive bits are equal, they are discarded; a sequence of 1,0 becomes a 1; and a sequence of 0,1 becomes a zero. It thus represents a falling edge with a 1, and a rising edge with a 0. This eliminates simple bias, and is easy to implement as a computer program or in digital logic. This technique works no matter how the bits have been generated."Fromhttps://en.wikipedia.org/wiki/Hardware_random_number_generator#Software_whitening

What would happen if the coin has a strong tendency to flip from the last toss?

Put random numbers into the next column and then sort both columns by the random number

Quote from: Bored chemist on 04/07/2021 22:51:53Put random numbers into the next column and then sort both columns by the random numberAs Mrs Beeton said, "first catch your rabbit..."Slightly off the subject (as always) when cooking with my chef son, he once told me to "Just....." and I asked "what exactly do you mean by "just" to which he replied "study and practice for 20 years, then just...." So, to construct 100 random numbers, start with a random number table, then just.....

and as far as I am concerned a set of 2-digit integers generated by Excel RAND is indeed adequately random,

However, Quantum Mechanics presents some evidence that probability is something inherently found in nature. So the answer to your problem is simple. Go down to the Physics lab and get their experimental set up of an electron being fired through some slits and impacting on a screen at the end. Draw a score board on the screen (like a darts board) and have a few games of quantum darts to generate some random numbers.

Common problem: I need to traceably randomise 100 patients for a clinical trial. So as they are recruited, I assign each one a random number from 00 to 99, then, say, give the trial drug to those with odd numbers and the placebo to the evens.How do I generate those random numbers? A. Take two 10-sided dice, one numbered 0 to 9 and the other, 00 to 90. Roll the dice and there's a random two-digit integer for each patient, with a 1 in 100 chance of it being any value from 00 to 99. B. put 100 counters in a hat, give it a good shake, draw one at a time and discard it: same probability of it being any value from 00 to 99.What is the probability that I will assign a given number to two patients? In case A, almost 1. In case B, zero.In case A I cannot guess what the next number will be, so that's really random. In case B, my guess will become more accurate as the numbers are assigned, and I know exactly what the 100th number will be, so it's not quite as random. It all depends on what you mean by "random".

While it would be possible to select 100 individuals randomly there is no way to achieve an accurate representation of the population of a country or of the Earth with just 100 individuals so random can not actually be achieved

Quote from: Europa on 21/07/2021 15:01:50While it would be possible to select 100 individuals randomly there is no way to achieve an accurate representation of the population of a country or of the Earth with just 100 individuals so random can not actually be achieved It's more like rounding error, representing population with less bit of information, rather than impossibility to get randomness.

Quote from: hamdani yusuf on 21/07/2021 23:02:04Quote from: Europa on 21/07/2021 15:01:50While it would be possible to select 100 individuals randomly there is no way to achieve an accurate representation of the population of a country or of the Earth with just 100 individuals so random can not actually be achieved It's more like rounding error, representing population with less bit of information, rather than impossibility to get randomness.Again there are too many human variables to represent the population with just 100 people. There are 195 countries in the World so this study would leave out entire groups