In: Statistics and Probability
Suppose a candy company representative claims that colored candies are mixed such that each large production batch has precisely the following proportions: 10 % brown, 10 % yellow, 20 % red,10 % orange,30 % green, and 20 % blue. The colors present in a sample of 459 candies was recorded. Is the representative's claim about the expected proportions of each color refuted by the data?
Color number of candies |
brown 43 |
yellow 106 |
red 89 |
orange 43 |
green 112 |
blue 66 |
---|
Step 1 of 10: State the null and alternative hypothesis.
Step 2 of 10: What does the null hypothesis indicate about the proportions of candies of each color?
Step 3 of 10: State the null and alternative hypothesis in terms of the expected proportions for each category
Step 4 of 10: Find the expected value for the number of chocolate candies colored brown. Round your answer to two decimal places.
Step 5 of 10: Find the expected value for the number of chocolate candies colored red. Round your answer to two decimal places.
Step 6 of 10: Find the value of the test statistic. Round your answer to three decimal places.
Step 7 of 10: Find the degrees of freedom associated with the test statistic for this problem.
Step 8 of 10: Find the critical value of the test at the 0.10.1 level of significance. Round your answer to three decimal places.
Step 9 of 10: Make the decision to reject or fail to reject the null hypothesis at the 0.10.1 level of significance.
Step 10 of 10: State the conclusion of the hypothesis test at the 0.10.1 level of significance.
Step 1 of 10:
Null hypothesis Ho:: expected proportion is as per company representative claims
Alternative hypothesis HA:: expected proportion is not as per company representative claims
Step 2 of 10: null hypothesis :Ho :pbrown =0.1 , pyellow =0.1 , pred =0.2 ; porange =0.1 ; pgreen=0.3 pblue =0.2
Step 3 of 10:: Alternative hypothesis HA :at least one proportion differs
Step 4 of 10:
expected value =np=459*0.1 =45.9
Step 5 of 10: =459*0.2 =91.8
Step 6 of 10:
applying chi square goodness of fit test: |
relative | observed | Expected | Chi square | ||
category | frequency(p) | Oi | Ei=total*p | R2i=(Oi-Ei)2/Ei | |
1 | 0.100 | 43.0 | 45.90 | 0.1832 | |
2 | 0.100 | 106.0 | 45.90 | 78.6930 | |
3 | 0.200 | 89.0 | 91.80 | 0.0854 | |
4 | 0.100 | 43.0 | 45.90 | 0.1832 | |
5 | 0.300 | 112.0 | 137.70 | 4.7966 | |
6 | 0.200 | 66.0 | 91.80 | 7.2510 | |
total | 1.000 | 459 | 459 | 91.1924 | |
test statistic X2 = | 91.192 |
Step 7 of 10:
degree of freedom =categories-1= | 5 |
Step 8 of 10:
for 0.1 level and 5 df :crtiical value X2 = | 9.236 |
Step 9 of 10: reject Ho
Step 10 of 10:
at least one proportion differs from stated