Question

The following sample data reflect shipments received by a large firm from three different vendors and the quality of those shipments. (You may find it useful to reference the appropriate table: chi-square table or F table)

Vendor	Defective	Acceptable
1	18		117
2	26		66
3	33		248

a. Select the competing hypotheses to determine whether quality is associated with the source of the shipments.

• H₀: Quality and source of shipment (vendor) are independent.; H_A: Quality and source of shipment (vendor) are dependent.

• H₀: Quality and source of shipment (vendor) are dependent.; H_A: Quality and source of shipment (vendor) are independent.

b-1. Calculate the value of the test statistic. (Round intermediate calculations to at least 4 decimal places and final answer to 3 decimal places.)

b-2. Find the p-value.

• p-value 0.10
• 0.05 p-value < 0.10
• 0.025 p-value < 0.05
• 0.01 p-value < 0.025

• p-value < 0.01

b-3. At the 5% significance level, what is your conclusion?

• Do not reject H₀; we cannot conclude that quality and source of shipment (vendor) are dependent.

• Reject H₀; we cannot conclude that quality and source of shipment (vendor) are dependent.

• Do not reject H₀; we can conclude that quality and source of shipment (vendor) are dependent.

• Reject H₀; we can conclude that quality and source of shipment (vendor) are dependent.

c. Should the firm be concerned about the source of the shipments?

• No

• Yes

Answer 1

The statistical software output for this problem is :

(a)

H₀: Quality and source of shipment (vendor) are independent.;

H_A: Quality and source of shipment (vendor) are dependent.

(b-1)

Test statistics = 15.179

(b-2)

P-value < 0.01

(b-3)

Reject H₀; we can conclude that quality and source of shipment (vendor) are dependent.

(c)

Yes