2-Sample t for Decrease Customer Order Cycle Time

Use 2-Sample t to demonstrate that average customer order cycle time decreases after a process improvement.

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

Example

Customer order cycle time is the number of days between a customer order and delivery of the product.

In this worksheet, Number of Days contains the customer cycle times. Process Change indicates whether the customer cycle times are before or after a process improvement.

C1	C2-T
`Number of Days`	`Process Change`
30	Before
27	Before
26	Before
32	Before
20	After
18	After

How-to

Choose Solutions Modules > Functions > Supply Chain KPIs, then select Launch.
Under Cycle Time, select Customer order cycle time.
Select Decrease customer order cycle time, then click OK.
Select 2-Sample t, then click OK.
From the drop-down list, select Both samples are in one column.
In Samples, enter the column of cycle time data.
In Sample IDs, enter the column that indicates whether the data are from before or after your process improvement.
Click 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 customer cycle time has decreased after the process change.
Click OK.

Tip

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