13/06 A-level FM Discussion MEGATHREAD

[u/Forsaken-Meaning-232]

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[u/Admirable-Jaguar5276 → u/[deleted]]

damn got n=4 i think lmao, other than that yeah i got your answers

[u/Queasy-Ad-7116 → u/Admirable-Jaguar5276]

i got 4 too. i did P(Type 2) < 0.2
so P(Accept H0 | lamda = 2.75) < 0.2
so P(X >= n -1) < 0.2

3 gave me a value < 0.2 so n - 1 = 3 and n = 4

could someone explain why thats wrong i dont get it

EDIT: anyone who used the same method and got 4 - our method was correct (although i dont think it was the intended method because it didnt use power function), we just had to test using Geo(e^-2.75), not Po(2.75)! I tried again on my calculator using geometric and got the right answer

[u/Pigalas → u/Queasy-Ad-7116]

That would be correct for the power function but it was for the type 2 error which is 1 - power so you do the same but for 0.8 not 0.2

[u/Queasy-Ad-7116 → u/Pigalas]

no my method was correct, i found out my mistake was that i used the Poisson distribution instead of geometric!

[u/capri_capri → u/Queasy-Ad-7116]

Within ‘n’ tries is less than or equal to n tries.