X $-$chart

$R-$ Chart

C$.$ Process capability

$P$ chart

C $-$ chart

Central Limit Theorem

Process capability

Run Test

Acceptance sampling

Benchmarking

Brainstorming

Statistical process control chart

Upper control limit

Lower control limit

O$.$ Out$-$of$-$control process

R$.$ Customer satisfaction

Q$.$ Customer choice analysis

P$.{?}^{\text{C}\text{u}\text{s}\text{t}\text{o}\text{m}\text{e}\text{r}\text{p}\text{a}\text{n}\text{e}\text{l}\text{s}}$

S$.$ $ Blog

T$.$ Tree diagram

A$.$ a chart that tracks the changes in percentages of a specified attribute over a period of time

B$.$ A test used to examine the points in a control chart to see if nonrandom variation is present

C$.$ A method of measuring random samples of lots or batches of products against predetermined standards

D$.$ a process in which one or more points in an SPC chart fall outside the control limits; out$-$of$-$control patterns can also be identified when pro$-$cess data exhibit certain specific trends even when all points fall within the control limits

E$.$ a line similar to the upper control limit$,$ but drawn at a prespecified distance below the mean value

F$.$ an approach for quantifying the relative importance that customers assign to the vari$-$ous features and components of products and services

G$.$ a theorem stating that the shape of the distribution of averages for samples follows a normal distribution even if the original distribution was very different

H$.$ a specific type of run chart calculated with well$-$defined statistical properties

I. a structured process for comparing the business practices of an organ$-$ization to the best practices that can be identified in other organizations $($partner firms, competitors, or suppli$-$ers$)$ or other divisions within a company

J$.$ a chart that shows how the process average changes over time

K$.$ a web site where an individual writes a commen$-$tary about a specific product, issue, or topic

L$.$ a measurement of how well the products and services that a firm supplies meet or exceed its customers' expectations

$M.$ is a measure of the relationship between the natural variation of the process and the specifications

N$.$ a line drawn at a prespecified dis$-$tance $($based on standard deviation units$)$ above the mean value; the line repre$-$sents the division between in$-$control and out$-$of$-$control processes.