Question

Computer software generated 500 random numbers that should look like they are from the uniform distribution on the interval 0 to 1. They are categorized into five groups:

1. less than or equal to 0.2
2. greater than 0.2 and less than or equal to 0.4
3. greater than 0.4 and less than or equal to 0.6
4. greater than 0.6 and less than or equal to 0.8
5. greater than 0.8.

The counts in the five groups are 113, 95, 108, 99, and 85, respectively. The probabilities for these five intervals are all the same. What is this probability? Compute the expected number for each interval for a sample of 500. Finally, perform the goodness of fit test and summarize your results.

Answer 1

Answer:

0.2 ; 100 ; 4.84

Step-by-step explanation:

Given that the probability of each of the 5 groups is the same :

Sum of probability = 1

Hence, Probability of each group = 1 / number of groups = 1 / 5 = 0.2

Expected number for each interval for a sample of 500 : ; X = 500

E(X) = X * P(x) = 500 * 0.2 = 100

Goodness of fit (X²) :

X² = Σ(X - E)² ÷ E

Groups :

113, 95, 108, 99, and 85

X : 113 ____ 95 ____ 108 ____ 99 _____ 85

(113 - 100)^2 / 100 = 1.69

(95 - 100)^2 / 100 = 0.25

(108 - 100)^2 / 100 = 0.64

(99 - 100)^2 / 100 = 0.01

(85 - 100)^2 / 100 = 2.25

(1.69 + 0.25 + 0.64 + 0.01 + 2.25) = 4.84