A.Zargari
Page 1
2/6/2016
Individual Project II (50 points): Please solve and submit your completed project by 225-2014 at 10:00 p.m.
1.
Explain the foundation of Shewhart’s notion of scientific approach and the basic
activities involved in developing means for satisfying the customers (in
approximately 100 words)
The foundation of Shewhart’s notion of scientific approach is SPC (Statistical
Process Controls), which is a powerful collection of problem-solving tools useful
in achieving process stability and improving capability through the reduction of
variability. The tools used in this collection are; Histogram or stem and leaf plot,
Check Sheet, Pareto chart, Cause and Effect diagram, Defect concentration
diagram, Scatter diagram and Control Chart.
2.
3.
4.
5.
Explain the Juran Trilogy, in approximately 50 words:
The trilogy is a process of quality control that is in 3 concepts; quality planning,
quality control and quality improvement. Planning is the strategic and tactical
goals, control is the prevention or to correct the unwanted or unexpected
changes, improvement is to create planned, predictable and manage change.
Briefly list and describe the purpose for basic tools for quality improvement
(Basic Process Improvement Toolbox).
a powerful collection of problem-solving tools useful in achieving process stability
and improving capability through the reduction of variability. The tools used in
this collection are; Histogram or stem and leaf plot, Check Sheet, Pareto chart,
Cause and Effect diagram, Defect concentration diagram, Scatter diagram and
Control Chart
Explain the properties of random variables
The properties of random variables the fact that their value is subject to
variations due to chance. A variable can take on a set of possible different
values. They are also note by two different characteristics, Discrete and
continuous. Discrete has a countable value and continuous has not limited value.
The data shown below are the times in minutes that successive customers had to
wait for service at an oil change facility. Using hand calculation and formula 1)
find sample mean and standard deviation, 2) construct a histogram, and 3) use
MINITAB to validate your findings and the histogram.
9.93
9.92
9.97
9.96
9.91
9.90
10.09
10.07
10.01
10.10
10.13
9.78
9.97
10.08
10.15
9.93
9.99
9.91
10.05
9.88
9.98
10.07
9.92
10.01
9.94
9.88
10.05
10.06
10.21
10.13
9.92
9.84
10.09
9.84
9.98
9.92
10.01
9.86
9.95
9.83
9.98
10.01
10.09
10.08
10.00
10.02
10.03
10.03
10.02
9.97
A.Zargari
Page 2
2/6/2016
Histogram of C1
Normal
12
Mean
StDev
N
10
9.989
0.09181
50
Frequency
8
6
4
2
0
9.8
9.9
10.0
C1
10.1
10.2
6.
If the probability that any individual will react positively to a drug is 0.8, what is
the probability that 4 individuals will react positively from a sample of 10
individuals?
Pr(X<x) = Sum of (n/t) .84 (1-.8)10-4 = .00636
7.
Suppose the average number of customers arriving at ATM during the lunch hour
is 12 customers per hour. The probability of exactly two arrivals during the lunch
hour is:
e-λ (λ12/x!) = (.2718-12) (122) /2! = .000442383
8.
In a sample of 100 items produced by a machine that produces 2% defective
items, what is the probability that 5 items are defective? (Calculate with binomial
distribution formula and verify your response using MINITAB).
Solve the question #8 using Poisson distribution formula and verify your
response using MINITAB.
Sum of (n/t) .025 (1-.02)100-5 = .0000000938982
9.
It is assumed that the inductance of particular inductors produced by ABC
Company is normally distributed. The  of inductors is = 20,000 mH, and  of
90 mH. If acceptable inductance range is from 19,750 mH to 20,200 mH. Using
both formula and MINITAB, determine the expected number of rejected inductors
in a production run of 10,000 inductors.
UL or LL –mu/ sigma= 19750 – 20000/ 90 = -2.77 20200-20000/ 90= 2.22
z= .9972
z = .9868
A.Zargari
Page 3
2/6/2016
10.
Explain Null Hypothesis, Alternative Hypothesis, Types of error, Significance
Level, Risk Level in hypothesis testing
Null hypothesis labeled as Ho is the basis for the argument but not proved
because it is to be the tested aspect of the hypothesis, Alternative is labeled H 1 is
the reverse or the challenge to the hypothesis, it is accepted when the null is
rejected. Types of errors, Type 1 is the rejecting of the null when it is actually true
and Type 2 is not rejecting the null when it needs to be rejected. Significance
level is the probability that an effect is not just because of chance it has a
significance that it had happened. Risk level is the alpha of the hypothesis test, it
the amount of risk that is taken when making the hypothesis that the null will not
be true or the alternative will not be true.
11.
Formulate the appropriate null hypothesis and alternative hypothesis for testing
that the starting salary for graduates with a B.S. degree in electrical engineering
is greater than $38,000 per year. The significance, or risk, is: What does  =
0.05 mean?
H0 = 38,000, H1 ≠ 38,000 α = .05 is the confidence level of the Hypothesis will
not be rejected. That is to say that the person making the Hypothesis is 95%
confident that it will not be rejected
12.
In a New York Times/CBS poll, 56 percent of 2,000 randomly selected voters in
New York City said that they would vote for the incumbent in a certain twocandidate race. Calculate a 95 percent confidence interval for the population
proportion. Discuss its implication. Carefully discuss what is meant by the
population, how you would carry out the random sampling, and what other factors
could lead to differences between the responses to the surveys and the actual
votes on the day of the election.
Sample X= 1120 N= 2000 Sample p = 0.5600
95% CI= (0.537921, 0.581903)
The implications of this CI are indicating there is 95% assurance that the 56% will
vote for the incumbent. The population is the 2000 randomly selected voters but
they are voters. I would carry out this experiment by asking individuals who vote in
the selected city who they would vote for.
13.
A random sample of 50 teaching assistants at the University of Iowa in the fall of
1996 indicated that 30 of them were planning to join the union for teaching
assistants. Calculate a 95 percent confidence interval for the proportion of
University of Iowa teaching assistants who are in favor of joining a union.
Sample X = 30 N = 50 Sample p = 0.6000
95% CI = (0.451794,
0.735922)
14.
Suppose that the number of wire-bonding defects per unit that occur in a
semiconductor device is Poisson distributed with parameter lambda (Mu or
A.Zargari
Page 4
2/6/2016
variance) of 4. Then, the probability that a randomly selected semiconductor
device will contain 2 or fewer wire-bonding defects is:
Poisson with mean = 4
x = 2 P(X = x) = 0.146525
15.
List and explain Deming’s 7 deadly diseases.
1. Lack of consistency of purpose to plan product and service: Management must
maintain constant interest in the purpose of the product and the plan.
2. Emphasis on short term profits: short term goals and short term profits become
short employment.
3. Mobility of management: the constant change in leadership will become
leaderless. There will be no one to leader the facility will the changing
hierarchy.
4. Personal review systems or incentives for management: Incentives for
management is pointless because the management make their own incentives
by building quality.
5. Use of visual figures only for management: This is also pointless because
management should be the visual figures to the subordinates.
6. Excessive medical costs: healthcare can be control through safety and
training.
7. Excessive liability costs: Lawyers and other legalities made this problem by
utilizing loopholes and other malefactors to bring such liable facets.
16.
Explain who, when, and why six sigma was developed. What is the focus of six
sigma?
The focus of Six Sigma is to bring the dispersion of the spread sample ranges; it
is a tool for quality and process improvement. It was developed by Motorola in
1987.
17.
Explain the DMAIC process and its relevance to quality.
DMAIC is a five step tool of the Six Sigma toolkit. Its steps consist of Define,
select the project and understand the metrics that will reflect the process of the
project, Measure, document the process and validate by measuring through
graphs and charts, Analyze isolate the top causes behind the issue the team is
taking on, Improve speaks for itself, improve by making the necessary changes,
Control maintain the changes and continuously improve.
18.
What is HISTOGRAM and why it is being used?
It is a frequency graph used to aid in visually viewing the frequency of samples.
19.
Define Probability Distribution. What is the difference between discrete and
continuous distributions? Provide Examples.
Probability Distribution is a statistical function that describes all the possible
values and likelihoods that a random variable can take within a given range.
A.Zargari
Page 5
2/6/2016
Discrete is the function in which is maintains a nominal finite value and continuous
is the function in which the value ranges from a value to infinity. A discrete
example is the rolling of dice ending a certain number of heads and tails. And
continuous is the varying weight of a person when it should be between a
specified number and another number and the variances between these number
would indicate the continuous example.
20.
Define Bernoulli trials and Poisson distributions and explain their uses in Quality.
Give example.
Bernoulli Trials are experiment having only two possible outcomes which are
success and failure. Example tossing a coin while heads is selected tails is the
result or vice versa. Poisson distribution is a probability distribution that occurs
when counting the number of occurrences of a rare event in a long series of trials
such as the number of visitors to an ATM in a given time range period.