# Inferential Statistic

• Pencipta
Topik
• #4382
HR Tiar

Two machines used in the same operation are to be compared. A random sample of 80 parts from the first machine yields 6 nonconforming ones. A random sample of 120 parts from the second machine shows 14 nonconforming ones.

a) Can we conclude that there is a difference in the output of the machines? Use a level of significance of 0.01.

b) Find a 95% confidence interval for the difference in the proportion of nonconforming parts between the two machines.

Melihat 1 balasan (dari total 1)
• Penulis
Balasan
• #4404
R-Stats
Keymaster

Diketahui $$\hat{p}_1=\frac{5}{80}=\frac{1}{20}$$ dan $$\hat{p}_2=\frac{14}{120}=\frac{7}{60}.$$ Untuk soal (a) hipotesis yang digunakan adalah \begin{aligned} \text{H}_0 &: p_2-p_1=0\\ \text{H}_1 &: p_2 – p_1 \neq 0 \end{aligned} Statistik ujinya adalah $z=\sqrt{\frac{(\hat{p}_1-\hat{p}_2)-d_0}{\hat{p}(1-\hat{p})\left( \frac{1}{n_1} + \frac{1}{n_2}\right)}}$ dimana $\hat{p}=\frac{x_1+x_2}{n_1+n_2}$

Melihat 1 balasan (dari total 1)
• Anda harus log masuk untuk menambahkan jawaban.