Find the rejected region in the problem of a biased die - Hypothesis

  • Thread starter Thread starter chwala
  • Start date Start date
chwala
Gold Member
Messages
2,825
Reaction score
413
Homework Statement
Kindly see attached question and mark scheme guide
Relevant Equations
##Bin (n,p)##
Consider the question below:

1626846377308.png


this (below) is the mark scheme for the problem, there were different methods given in the mark scheme but i was interested on this one only...

1626846432252.png


Now onto my question, How did they calculate ##P(X≥10)##=##1-P(X≤9)##=##0.055##...?

In attempting to understand the question i went ahead and looked at a similar problem (attached below); i.e

1626846784214.png


and i could see from my analysis that, the highlighted value could have been found using the steps below:
##P(x≥4)=1- [ P(x=0) +P(x=1)+P(x=2)+P(x=3)]##
=## 1- [0.1615+0.3230+0.2907+0.1550]##
=##1-0.9302##
=##0.0698##
ok is this correct? if so going back to our problem, do we use the same approach? or there is a shorter way...
This is the only part that i need clarity. I should be able to come to the deduction on whether to reject or accept null hypothesis.
 
Last edited:
Physics news on Phys.org
Yes, this is the way to compute it.
 
Orodruin said:
Yes, this is the way to compute it.
Thanks, implying that a student would have a lot of computation work to do (with calculator) to realize ##P(X≥10)## and ##P(X≥11)##... and then come to some conclusion... Phew!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top