independently. In general, higher-order interactions are confounded with main effects or lower-order
interactions. Because higher order interactions are rare, usually you can assume that their effect is
minimal and that the observed effect is caused by the main effect or lower-level interaction.
Full Factorial – A full factorial design of experiment (DOE) measures the response of every possible
combination of factors and factor levels. These responses are analyzed to provide information about
every main effect and every interaction effect. A full factorial DOE is practical when fewer than five
factors are being investigated. Testing all combinations of factor levels becomes too expensive and
time-consuming with five or more factors.
Gage Repeatability & Reproducibility (Gage R&R) – A measurement system evaluation to
determine equipment variation and appraiser variation. This study is critical to ensure that the
collected data is accurate.
Gantt Chart – A Gantt chart is a powerful and preferred visual reporting device used for conveying a
project’s schedule. A typical Gantt chart graphically displays the work breakdown, total duration
needed to complete tasks, as well as %completion. The Gantt chart itself will not display level of
effort, and is not an effective planning tool on its own. Today, Gantt Charts may be integrated with
other spreadsheet-type reporting devices that convey additional information related to project
planning. Furthermore, Gantt Charts are often enhanced with functionality that includes the
identification of relationships between tasks, and the ability to dynamically change task attributes.
General Linear Model – General Linear Model (GLM) is a tool used to analyze the participation of
each x’s in creating defects for Project Y. This can be used to compliment the result of a Pareto
Chart where the 80:20 ratio is analyzed and worked upon.
Also in cases where none of the Potential x’s could prove its significance as a part of the ‘Analyze’
phase, this tool can be used to enquire/attain information as to the contribution of each potential x’s
in creating a defect for your Project Y.
Green Belt – An employee of an organization who has been trained on the improvement
methodology of Six Sigma and will lead a process improvement or quality improvement team as
‘part’ of their full time job. Their degree of knowledge and skills associated with Six Sigma is less
than that of a Black Belt or Master Black Belt.
GRPI Model – GRPI stands for four critical and interrelated aspects of teamwork: goals, roles,
processes, and interpersonal relationships, and it is a tool used to assess them.
Hawthorn Effect - Improved process data that results from process operators who know their
process performance is being measured and exercise more care in the execution of the process
than would normally be done.
Histogram – In statistics, a histogram is a graphical representation showing a visual impression of
the distribution of data.
Hypothesis – When used as a statistical term, it is a theory proposed or postulated for comparing
means and standard deviations of two or more data sets. A “null” hypothesis states that the data
sets are from the same statistical population, while the “alternate” hypothesis states that the data
sets are not from the same statistical population.
Hypothesis Tests, Alternative – The hypothesis that is accepted if the null hypothesis is disproved.
The choice of alternative, hypothesis will determine whether "one-tail" or "two-tail" tests are
appropriate.