Six Sigma

The short-term Z-score is 4.0 after a process improvement effort. What will the long-term Z-score be?

2.5

In a box plot, the interquartile range (IQR) contains _________ of data studied.

50%

If one is checking measurements against a reference/standard, she is doing a(n) ___________ check.

Accuracy

The consistency in the inspection/review process can be measured by:

Attribute MSA

The problem in accuracy, linearity, and/or stability result in the average of the data being below or above the true value. The distance between the average and true value is known as:

Bias

At a customer service center, total incoming calls = 10,000 during a month. Total dropped calls before they were answered = 1,333. What distribution is suitable for process capability estimation?

Binomial

The ratio and interval scale of data are linked to the___________ type of data.

Continuous

Data is important for gaining knowledge about:

Customer needs, Problems, Processes

What is a technique for organizing data into different groups for analysis?

Data Stratification

A p-chart is used for _________ and a u-chart is for _______.

Defective data; Defect data

A decision-making activity is represented by a _____________ symbol in the detailed process map.

Diamond

The _________ of individual values can be a useful alternative to the histogram.

Dot plot

Attribute agreement analysis is different from measurement system analysis. T or F

False

Long-term process capability is subject to special cause variation only. T or F

False

Measurement system analysis is used for continuous data only. T or F

False

The 5 Whys approach is a problem-solving technique.T or F

False

Value stream mapping (VSM) does not include suppliers and customers. T or F

False

If % tolerance GR&R ≤ 10%, then the measurement system (MS) is:

Ideal (If the % tolerance GR&R ≤ 10%, then the MS is ideal. If the % tolerance GR&R = 10%-20%, then the MS is acceptable. If the % tolerance GR&R = 20%-30%, then the MS is marginal. If the % tolerance GR&R > 30%, then the MS is poor.)

Process maps help in characterizing the functional relationships of various:

Inputs and Outputs

The x-axis of a histogram contains the ______________scale of data.

Interval

Lead time for a delivery process is the time elapsed between when a product is ordered and when the product:

Is delivered

In attribute agreement analysis, the _________ is used to measure inter/intra-rater agreement.

Kappa statistic

A distribution that best fits the process data is selected based on p-value. What distribution should be selected for process capability analysis with a confidence level of 95%? 1. Weibull distribution, p-value < 0.003 2. Lognormal distribution, p-value = 0.075 3. Exponential distribution, p-value < 0.005 4. Normal distribution, p-value < 0.05

Lognormal (For lognormal distribution, p-value = 0.075 > 0.05 (α-risk). α-risk = 1 - confidence level = 1 - 0.95 = 0.05.)

__________ distribution is the non-normal distribution for continuous data

Logonormal

The variation in the measured data set due to the way measurements are being taken is known as _______________ error.

Measurement

What method is used to know if the data is accurate and precise?

Measurement System Analysis

The preferred measure of central tendency of skewed continuous data or ordinal data is:

Median

An uncontrolled or difficult-to-control variable that is identified in a fishbone diagram is known as:

Noise

Which of these is not continuous data?

Number of Students

The Cpk will be negative if the mean of a process output is:

Outside the customer specification limits

Process capability is assessed by comparing the Voice of the ___________ to the Voice of the ___________.

Process; Customer

In measurement system analysis, precision can be divided into ___________ and _____________.

Repeatability; reproducibility

The characteristics of the appropriate measure are sufficient, relevant, _______________, and contextual.

Representative

What term is used for the ability of a measurement system to detect small changes or granularity in the characteristics of a process?

Resolution and Discrimination

What should you do first if the high variation in data is coming from the measurement system, assuming the equipment has no issue?

Retrain the operators

For a normal distribution, the mean, median, and mode are same. If the mean is greater than the median, the distribution is:

Right Skewed

Which of the following is a high-level process map?

SIPOC

What is the technique/process used in statistical analysis to get a small group of data to represent the whole population of data?

Sampling

Attribute process capability is always assessed based on long-term data, as it requires ____________ samples to get a good estimate statistically.

So many

What is not a focus of the FMEA approach?

Solving problems

For Cpk assessment, the process should be _________ and data must be _______.

Stable; normal

The X-Y matrix is a prioritization tool for the potential Xs based on the:

Team's collective opinions

A data set is considered to be normal with a 95% confidence level if

The p-value is greater than .05

If Cpk upper (Cpu) = 2.0 and Cpk lower (Cpl) = 0.83, what can you conclude?

The process is not stable because Cpk is less than 1.33

A data collection plan is used mostly to gather passive data. T or F

True

A process is not stable if process data show any special cause variation. T or F

True

A spaghetti diagram/plot is used to trace the movement of products, papers/documents, and people. T or F

True

An operational definition is a clear, concise description of a parameter or variable of a process. T or F

True

If the data distribution is skewed, range is used to estimate variability of data. T or F

True

In the Six Sigma approach, the current process capability is the key output of the Measure Phase. T or F

True

Measurement system analysis also includes the environment. T or F

True

The purpose of the Measure Phase is to identify the gap in process capability in order to meet a target or the Voice of the Customer (VOC). T or F

True

The following customer service time data are collected at a bank branch for 20 subgroups, for which there are 6 customers per subgroup. Overall mean = 2.5 min., and average range (R-bar) = 1.0 min. Upper and lower specification limits are 1.5 min and 4.0 min. The probability of customers served below 1.5 min is greater than that of customers served above 4.0 min

True (Zl = (LSL - mean)/std. dev. Zu = (mean - USL)/std. dev. std. dev. = R-bar/d2 = 1.0/2.534 = 0.4 min (approx.) (d2 = 2.534 for subgroup size of 6) Zl = (1.5 - 2.5)/0.4 = 1.0/0.4 = -2.5, Probability = 0.621% Zu = (4 -2.5)/0.4 = 1.5/0.4 = 3.75, Probability = 0.009% Note: Use the IASSC reference document for the d2 value (Control charts - Table of constants) and for probability from the Z-table.)

Value-added flow analysis helps with identifying:

Value added activities, non value added activities that are necessary, non value added activities that are not necessary