2- The Measure Tollgates

The second step of the application of Six Sigma DMAIC is Measure.It is in this second step that the current sigma performanceis calculated, sometimes at a more detailed level than occurred at the strategic level of Six Sigma.

There are two major Measure Tollgates, the creation of the data collection plan and the implementation of the data collection plan.

1. Creation of the Data Collection Plan

The data collection plan has 7 columns. Each column has an important role in helping the team calculate the last column, baseline sigma.

Below are listed the columns and their definition:

• What to measure: In the first column of the data collection plan, the team should take the requirements determined in the Define stage of DMAIC and place them in this first column.

• The type of measure:This second column determines if the project team will collect too much or too little data.

Continuous data refers to data that exists on a continuum such as height, weight, minutes, days, length, and so on.Continuous data is preferred over discrete data because it tells us more about a process.

• Operational definitions: The operational definition is a description of something where all involved have a common understanding with no ambiguity over what is being described.

• Targets/specifications: The target measure is the customer’s ideal performance of the product or service.

• Data collection forms: There are two types of data collection forms. One is used for discrete data and the other used for continuous data.

There are four steps to using a discrete data collection form:

1. Determine what a defect is.

2. Determine categories of defects.

3. Determine the time frame for data to be collected.

4. Determine a grid for data to be collected.

For continuous data, the Six Sigma project team should use a frequency distribution check sheet. This type of check sheet tracks the number of occurrences for a given event for each measurement or series of measurements

• Sampling: Sampling is the process of taking only a proportion of the total population of available data, when measuring the entire population would either be too expensive or take too much time.

To ensure that sampling is done correctly, the sample must be representative of the larger population and be taken randomly.

2. Implementation of the Data Collection Plan

The second tollgate is taking the Data Collection Plan and implementing the plan to generate the baseline sigma:

• Calculating baseline sigma: There are several methods to calculate baseline sigma. The easiest way is to determine what a unit, defect, and opportunity is for your project ( defects per million opportunities)

Please see below to understand