Lovegrove Mathematicals

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Integram Theorem

Integram Theorem

Proof

Proof

When ω(g1)=1, this reduces to Laplace's Law of Succession. If it is required to look more than one observation ahead, it is not possible to use the Law of Succession but the Integram Theorem can be used, instead.

Example

A question, capable of being answered "Yes" or "No", is asked of 10 people. 7 reply "Yes" and 3 reply "No".

What is the Likeliness that

  1. If one more person is asked that question then the reply will be "Yes";
  2. If two more people are asked the question they will both reply "Yes"?
Solution

Represent "Yes" by "1" and "No" by "2". The underlying set is then S(2) and the given integram is g2=(7,3).

Part 1. The required integram is g1=(1,0), so we need LS(2)((1,0)|(7,3)). We are looking only one observation ahead, so the Law of Succession may be used.

We then get LS(2)((1,0)|(7,3))=(7+1)/(10+2)=8/12=2/3

Part 2. The required integram is g1=(2,0), so we need LS(2)((2,0)|(7,3)). We are looking two observations ahead, so the Law of Succession cannot be used. We shall use the Integram Theorem, instead.

We have g1+g2=(2,0)+(7,3)=(9,3), and so

Hence LS(2)((2,0)|(7,3))=(1.120/220).(11/13)=6/13

Note that (2/3)2=4/9 (=0.4444...), not 6/13 (=0.4615...), so it would be incorrect -when answering Part 2- to use the Law of Succession (as in Part 1) and then square the result: doing so would be equivalent to assuming that the best estimate of a square is the square of the best estimate, which is the same logical trap that the Perfect Cube Factory falls prey to.