A die is said to be fair if the probability of rolling the n
A die is said to be fair if the probability of rolling the number i is pi=1/6 for i=1,…,6. You roll a die 60 times with the following outcome.
(a) Calculate the test statistic X2 for the test
using the formula
X2=(OiEi)2Ei.
X2= ______
(b) Use the R function pchisq() and the value of the test statistic from (a) to find the p-value for the test in (a).
p-value = ______
| i | 1 | 2 | 3 | 4 | 5 | 6 | 
|---|---|---|---|---|---|---|
| Oi | 15 | 9 | 9 | 10 | 6 | 11 | 
Solution
A)
Doing an observed/expected value table,          
 O   E   (O - E)^2/E  
 15   10   2.5  
 9   10   0.1  
 9   10   0.1  
 10   10   0  
 6   10   1.6  
 11   10   0.1  
           
 Using chi^2 = Sum[(O - E)^2/E],          
           
 chi^2 =    4.4   [ANSWER]
**********************  
           
 b)
As df = a - 1,           
           
 a =    6      
 df = a - 1 =    5      
           
 Thus, the p value is          
           
 p =    0.493373524   [ANSWER]

