2 Proportions for Increase Customer Satisfaction

Use 2 Proportions to demonstrate that the proportion of positive survey responses increases after a process improvement.

This example applies to the Customer Contact Center Module. For more information, go to www.minitab.com/customer-contact-center-module.

Example

A yes/no survey question is one where the response can be one of 2 possible values.

In this worksheet, Yes Responses Before and Yes Response After contain the number of positive responses before and after a process improvement. Total Response Before and Total Responses After contain the total number of survey responses before and after the process improvement. You can enter these observations directly in the dialog box instead of storing them in the Minitab worksheet.

C1	C2	C3	C4
`Yes Responses Before`	`Total Response Before`	`Yes Response After`	`Total Responses After`
466	744	549	788

How-to

Choose Solutions Modules > Functions > Customer Contact Center KPIs, then select Launch.
Under Customer Satisfaction, select Yes/no survey.
Select Increase customer satisfaction, 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 positive responses before the process improvement as Sample 1. Enter the number of positive responses after the process improvement as Sample 2.
In Number of trials, enter the total number of responses before the process improvement as Sample 1. Enter the total number of responses 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 number of positive responses has increased after the process change.
Click OK.

Tip

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