2 Proportions for Improve Freight Bill Accuracy

Use 2 Proportions to demonstrate that the proportion of freight bill accuracy increases after a process improvement.

This example applies to the Supply Chain Module. For more information, go to www.minitab.com/supply-chain-module.

Example

A freight bill, or freight invoice, includes the shipping details and fees for shipments. Freight bill accuracy is the proportion of accurate freight bills.

In this worksheet, Accurate Bills Before and Accurate Bills After represent the number of accurate bills before and after a process improvement. Total Orders Before and Total Orders After represent the total number of bills before and after the process improvement.

With summarized data, you enter the data values instead of the column identifiers.

`Accurate Bills Before`	`Total Orders Before`	`Accurate Bills After`	`Total Orders After`
909	1000	1142	1235

How-to

Choose Solutions Modules > Functions > Supply Chain KPIs, then select Launch.
Under Quality, select Freight bill accuracy.
Select Improve freight bill accuracy, then click OK.
Select 2 Proportions, then click OK.
From the drop-down list, select Summarized data.
In Number of events, enter the number of accurate bills before the process improvement as Sample 1. Enter the number of accurate bills after the process improvement as Sample 2.
In Number of trials, enter the total number of bills before the process improvement as Sample 1. Enter the total number of bills after the process improvement as Sample 2.
Select Options. In Alternative hypothesis, select Difference < hypothesized difference. The hypothesized difference defines your null hypothesis. By default, the hypothesized difference = 0. This one-sided test has greater power to detect whether the freight bill accuracy increased after the process change.
Click OK.

Tip

For more information about this analysis, click Help in the main dialog box.