Practice Test Geeks(SPC) Statistical Process Control Certification Practice Test
← All SPC Flashcard Decks

Data Collection & Interpretation Flashcards

7 cards from real SPC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Data Collection & Interpretation flashcards as text

  1. Which of the following BEST describes the difference between precision and accuracy in measurement?

    Answer: Precision is consistency of repeated measurements; accuracy is closeness to the true value

    Precision describes how repeatable a measurement is, while accuracy describes how close the average measurement is to the actual true value.

  2. When plotting data on a run chart, a run of 7 or more consecutive points on one side of the median typically signals:

    Answer: A non-random pattern suggesting a process shift

    Seven or more consecutive points on one side of the median is a run rule violation indicating a likely shift in the process center.

  3. Resolution in a measurement instrument refers to:

    Answer: The smallest increment the instrument can detect and display

    Resolution is the finest discrimination the instrument can make, and insufficient resolution can mask real process variation.

  4. A scatter diagram is used during data interpretation to:

    Answer: Examine the relationship or correlation between two variables

    A scatter diagram plots pairs of variables to visually assess whether a relationship or correlation exists between them.

  5. If sample data for an Xbar-R chart are collected in subgroups of n = 4, the expected distribution of subgroup means is:

    Answer: More normally distributed than individual values due to the central limit theorem

    The central limit theorem states that averages of samples tend toward normality even if individual measurements are not normally distributed.

  6. Which of the following is an example of an assignable (special) cause detected during data review?

    Answer: A single measurement exceeding the upper control limit after a tool change

    A point outside the control limits linked to an event like a tool change is a special cause that requires investigation and corrective action.

  7. Data truncation in process measurement occurs when:

    Answer: Values beyond instrument range or specification limits are recorded as the limit value

    Truncation happens when a gage or system caps readings at a fixed boundary, distorting the true distribution tail.