# Probability question

I came across the following problem related to clinical trials. Within each family of a clinical trial, there are probability associated with individual indications within that family.

For instance,

 1 2 3 4 5 6 7 Indications Region POS Indication1 US 100% Outside US 95% Indication2 Worldwide 81% Indication3 Worldwide 68% Indication4 Worldwide 63% 

I simulate scenarios by generating uniformly distributed random number in the interval [0,1]. If the random number is less than equal to 63%, all indications 1 through 4 become applicable. Similarly, when the number is less than equal to 81%, then only Indication 1 through 2 become applicable. So these are tiered probabilities such that Indication4 cannot be successful without the occurrence of indications 1,2, and 3.

What do these probabilities actually represent? Are these conditional probabilities? What would be the probability density function that would add to 1?

Thanks

Note by Susan P
6 months, 2 weeks ago

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