Conduct the hypothesis test and provide the test statistic, critical value and P

Question

Conduct the hypothesis test and provide the test statistic, critical value and P-value. and state the conclusion. A person randomly selected 100 credit card purchases and recorded the cents portions of those amounts. The table below lists those cents portions categorized according to the indicated values. Use a 0.025 significance level to test the claim that the four categories are equally likely. The person expected that many checks for whole dollar amounts would result in a disproportionately high frequency for the category, but do the results support that expectation?

Explanation / Answer

The answers are highlighted in bold part:

> cf <- c(62,11,12,15)
> prop.test(cf,rep(100,4))

4-sample test for equality of proportions without continuity
correction

data: cf out of rep(100, 4)
X-squared = 97.8133, df = 3, p-value < 2.2e-16
alternative hypothesis: two.sided
sample estimates:
prop 1 prop 2 prop 3 prop 4
0.62 0.11 0.12 0.15

> qchisq(1-0.025,3)
[1] 9.348404

The test statistic value is 97.8133, critical value is 9.3484, and the p-value is 0.

Since the null hypothesis is that all the four cells have equal count, and we reject the null hypothesis, it can be concluded that there is a disproportionately high frequency for the first category.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.