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� Where Quality Assurance checks whether standards and procedures are being followed, Quality Control uses specific measurements to check if the project and its processes are in control.
� While quality assurance is primarily done during the Executing process group, quality control is done during the Monitoring and Controlling process group of the project and its focus is on the correctness of the work.
� Control quality is used during executing and closing phases to formally demonstrate, with reliable data, that the sponsor/customer’s acceptance criteria have been met.
B. Identify the deviation from the mean of the control chart
C. Show team responsibilities
D. Identify potential factors causing an overall effect
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Control Charts
� Control Chart
� A data gathering tool to show when a process is subject to cause variation or in a out-of-control condition
� Illustrates how a process behaves over time
� The process is statistically ‘out-of-control’ in either of these two conditions:� A data point falls outside the upper or lower control limit –Out of Control condition.
� Non-random data points that are still within the upper and lower control limits, such as the ‘rule of seven’
� ‘Rule of seven’ – where non-random data points are grouped together in a series of seven, on one side of the mean. This indicates that the process may be out-of-control and needs to be investigated
� An ‘out-of-control’ process lacks consistency and predictability
You are involved in monitoring specific project results to determine whether they comply with relevant quality standards. You are using the control chart to illustrate how the process is behaving over time. You have constructed your chart and that all data points are within upper and lower control limits of chart. In addition, seven consecutive data points are observed, to be one side of the mean. Which of the following is your BEST plan of action?
A. Compare results from the last quality management plan
B. No additional actions is needed, as the process is within control
C. Adjust the mean based on the observed data points
� Pareto Chart� A Pareto Chart is a type of histogram, with data displayed in the form
of bars or columns
� The higher the bar, the more frequent the problem
� Studies show that 80% of the problems are due to 20% of the causes, so identifying and addressing the root causes of the most frequent problems makes the biggest impact on quality
� Helps focus attention on the most critical issues
Which of the following statements are true regarding the Pareto diagrams?
A. Pareto diagram involves using mathematical techniques to forecast future outcomes based on historical results
B. Pareto diagrams use statistical measurements to identify the most important problems through different measurement scale; i.e. frequency, cost, etc and directs attention and efforts to most significant problems and /or opportunities
C. Pareto diagram illustrate the relationships between two variables
D. Pareto diagrams are created by randomly selecting random portions of a population for inspection
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Control Quality
� Run Chart� Shows the history and trend of variation over time
� Often used to monitor technical, cost, and schedule performance
� Scatter Diagram� Shows the pattern of relationship between two variables, to see if they
are related. For example, if the quality of the wood is changed, so has the strength of the tables, a scatter diagram might be used to see if the two are related
Y
X
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Control Quality Monitoring and Controlling
Quality Management
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You are the project manager at a large automaker in Japan. Your project involves designing the next generation four wheel drive Sports Utility vehicle for the Asian market. Your project team is attempting to determine the right combination of suspension, tires and chassis that will ensure the stability of SUV at high speeds. Currently, you would like to measure the association between the two vehicle's - tire size and overall stability. Which of the following diagrams can you use?
� Statistical Sampling� Choosing part of a population for inspection to check for entire batch
acceptance
� Inspection� Physical examination to determine conformance to standards
� Also called ‘reviews’, ‘peer reviews’, ‘audits’, and ‘walkthroughs’
� Results of an inspection include measurements
� Defect Repair Review� Action taken to ensure that product defects are
repaired and brought into compliance with requirements
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Which of the following are tool/ technique of Perform Quality Control that involves measuring or testing results to determine whether they confirm to the requirements and quality standards?
� Two events are said to be Mutually Exclusive if they cannot both occur in a single trial, for example tossing a coin once cannot result in both a ‘head’ and a ‘tail’
� Normal Distribution� A Normal Distribution is the most common probability density
distribution chart, in the shape of a bell curve, used to measure variations
� Statistical Independence� The probability of one event occurring does not affect the probability
of another event occurring( for example the probability ofthrowing a 6 on a die does not affect the probability of getting a 5 on the next throw)
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Control Quality
� Some Statistical Concepts
� Standard Deviation (or ‘Sigma’)� The Standard Deviation is a measure of a range, also sometimes stated
as a measure of how far you are from the mean
� For example, (P – O ) / 6 is the formula for standard deviation using optimistic, pessimistic and most likely estimates as described in Project Time Management
� 3 or 6 Sigma� This represents the quality level that a company is trying to achieve
� 6 sigma represents less than 1.5 problems out of 1,000,000 and 3 sigma represents about 2,700 problems per 1,000,000
� 6 sigma is therefore a higher quality level than 3 sigma