Question description
Homework
Assignment 7
Due in Week 8 and worth 30 points
The
experiment data in below table was to evaluate the effects of three variables
on invoice errors for a company. Invoice errors had been a major contributor to
lengthening the time that customers took to pay their invoices and increasing
the accounts receivables for a major chemical company. It was conjectured that
the errors might be due to the size of the customer (larger customers have more
complex orders), the customer location (foreign orders are more complicated),
and the type of product. A subset of the data is summarized in the following
Table.
Table: Invoice Experiment Error
Customer Size
Customer Location
Product Type
Number of Errors
–
–
–
15
+
–
–
18
–
+
–
6
+
+
–
2
–
–
+
19
+
–
+
23
–
+
+
16
+
+
+
21
Customer Size: Small (-), Large (+)
Customer Location: Foreign (-), Domestic (+)
Product Type: Commodity (-), Specialty (=)
Reference: Moen, Nolan, and
Provost (R. D. Moen, T. W. Nolan and L. P. Provost. Improving Quality through Planned Experimentation. New York:
McGraw-Hill, 1991)
Use the date in table above and
answer the following questions in the space provided below:
1. What is
the nature of the effects of the factors studied in this experiment?
2. What
strategy would you use to reduce invoice errors, given the results of this
experiment?
