John M Awbrey Page 1 3/15/2016 IP2 IET 603 Mikey Awbrey M1014968 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) PDCA, Plan Do Check Act. Plan – set up experiment or plan for improvement. Do – Carry out plan from previous step. Check – Study results. Act – Adopt, abandon, or adapt change based on results. 2. Explain the Juran Trilogy, in approximately 50 words: Quality Planning, Quality Control, Quality Improvement. Quality planning – identify need and develop plan for process. Quality control – measure and observe process. Correct significant differences. Quality Improvement – Identify opportunities for improvement and provide remedies. 3. Briefly list and describe the purpose for basic tools for quality improvement (Basic Process Improvement Toolbox). Check Sheet – Collect discrete data about a process during use Cause-and-Effect diagram – quickly see the likely results of a cause Control Chart – check if process is in control, process capability Histogram – quickly identify patterns Pareto Chart – find significant many and insignificant few Scatter Diagram – graphically represent collected data Run Chart – easily collect data in simple numeric form 4. Explain the properties of random variables A Random variable is the numeric description of the outcome of an experiment taken from Ding & Yang Powerpoint. Random variables can be discrete or continuous. They are also able to be dependent or independent. A discrete random variable is a count, or a pass fail, represented as integers. Continuous variables can be any number from - to . Independent variables are variables which can change on their own, such as X in a linear line equation Y = kX + m. Dependent variables are numbers whose values change based on another one such as Y in the example before. 5. 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) John M Awbrey Page 2 3/15/2016 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 I used excel to help make the hand calculations faster. Included next to each part is the excel formula used. 9.78 =(A1-$D$3)^2 0.043681 9.83 n SUM MEAN 0.025281 Variance STD DEVIATION 9.84 50 499.45 9.989 0.022201 0.00843 0.091812809 9.84 =COUNT(A:A) =SUM(A:A) =C3/B3 0.022201 =SQRT(G3) 9.86 0.016641 =SUM(F:F)/(B3-1) 9.88 0.011881 9.88 0.011881 9.9 0.007921 9.91 0.006241 9.91 0.006241 9.92 0.004761 9.92 0.004761 9.92 0.004761 9.92 0.004761 9.93 0.003481 9.93 0.003481 9.94 0.002401 9.95 0.001521 9.96 0.000841 9.97 0.000361 9.97 0.000361 9.97 0.000361 9.98 8.1E-05 9.98 8.1E-05 9.98 8.1E-05 9.99 1E-06 10 0.000121 10.01 0.000441 John M Awbrey Page 3 10.01 10.01 10.01 10.02 10.02 10.03 10.03 10.05 10.05 10.06 10.07 10.07 10.08 10.08 10.09 10.09 10.09 10.1 10.13 10.13 10.15 10.21 3/15/2016 0.000441 0.000441 0.000441 0.000961 0.000961 0.001681 0.001681 0.003721 0.003721 0.005041 0.006561 0.006561 0.008281 0.008281 0.010201 0.010201 0.010201 0.012321 0.019881 0.019881 0.025921 0.048841 The following Minitab results confirm my calculations. Standard Deviation of C1 Standard deviation of C1 = 0.0918128 Mean of C1 Mean of C1 = 9.989 Sum of C1 Sum of C1 = 499.45 Number of Rows in C1 Total number of observations in C1 = 50 John M Awbrey Page 4 3/15/2016 Histogram of C1 Normal 12 Mean StDev N 10 9.989 0.09181 50 Frequency 8 6 4 2 0 6. 9.8 9.9 10.1 10.2 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? P=0.8 X=4 N=10 š p(x) = ( ) š š„ (1 − š)š−š„ š„ n! p(x) = š š„ (1 − š)š−š„ š„! (š − š„)! 10! p(x) = 0.84 (1 − 0.8)10−4 4! (10 − 4)! 5040 p(x) = 0.4096(0.000064) 24 p(x) = 0.005505 0.55% The following is Minitab result Probability Density Function Binomial with n = 10 and p = 0.8 x 4 10.0 C1 P( X = x ) 0.0055050 John M Awbrey 7. Page 5 3/15/2016 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: š =12 X=2 š −š šš„ p(X = x) = š„! š −12 122 p(X = x) = 2! p(X = x) = 0.00044238 0.044% The following is the minitab result Probability Density Function Poisson with mean = 12 x 2 8. P( X = x ) 0.0004424 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. N = 100 P = 0.02 X=5 š p(x) = ( ) š š„ (1 − š)š−š„ š„ n! p(x) = š š„ (1 − š)š−š„ š„! (š − š„)! 100! p(x) = 0.025 (1 − 0.02)100−5 5! (100 − 5)! 9034502400 p(x) = 0.0000000032(0.1467159029466343) 120 p(x) = 0.0353468 3.53% The following is the minitab result Probability Density Function Binomial with n = 100 and p = 0.02 x 5 P( X = x ) 0.0353468 John M Awbrey 9. Page 6 3/15/2016 It is assumed that the inductance of particular inductors produced by ABC Company is normally distributed. The ļ of inductors is = 20,000 mH, and ļ³ of 90 my. 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. ļļ ļ½ļ ļ²ļ°ļ°ļ°ļ°ļ ļ³ļ ļ½ļ ļ¹ļ°ļ LSL = 19750 USL = 20200 N = 10000 šæššæ − µ ššæššæ = š 19750 − 20000 ššæššæ = 90 šš³šŗš³ = š. šššš = š·š³šŗš³ šššæ − µ ššššæ = š 20200 − 20000 ššššæ = 90 ššššæ = 0.9868 šššš = š − šššš = š. šššš Pfailure = PUSL + PLSL Pfailure = 0.0028 + 0.0132 šššš¢š„š®š«š = š. ššš nššš¢š„ = š§(šššš¢š„š®š«š ) nššš¢š„ = ššššš(š. ššš) ššššš = ššš The following is the minitab result Cumulative Distribution Function Normal with mean = 20000 and standard deviation = 90 x 19750 20200 P( X <= x ) 0.002737 0.986866 10. Explain Null Hypothesis, Alternative Hypothesis, Types of error, Significance Level, Risk Level in hypothesis testing Null Hypothesis – the result that you are trying to disprove Alternative Hypothesis – what to except is the null hypothesis is false John M Awbrey Page 7 3/15/2016 Types of error – Type 1 occurs when null hypothesis is rejected when it should have been rejected. Type 2 is when the null hypothesis is accepted when it should have been rejected. Significance level – The probability of wrongly rejecting the null hypothesis. Probability of a type 1 error. Risk Level – The probability of wrongly accepting the null hypothesis. Probability of a type 2 error. 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 ļ” = 0.05 mean? H0 ≤ 38,000 H1 > 38,000 ļ” = 0.05 CI = 100(1-ļ”)% = 95% ļ” is the significance level of the test and the probability of the type 1 error. This is the probability that our null hypothesis is true. Confidence Interval (CI) is the probability that our alternative hypothesis is true. 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. The poll implies that the majority of the voters would vote for the incumbent in question. The population that we are estimating for is all of the voters, not only the ones surveyed. The best way to randomly sample the voters is to select people at random from different areas in the voting district. This should ensure the correct diversity to estimate the population. Potential problems with the sampling could be that only a certain demographic of people were polled. There could be outside factors such as political scandal that could change the minds of voters before election day. CI = 95% P = 56% N = 2000 X = P*N = 1120 Multiplier for 95% CI = 1.96 = z š(1 − š) š¶š¼ = š ± š ∗ √ š John M Awbrey Page 8 3/15/2016 0.56(1 − 0.56) 2000 šŖš° = š. šš ± š. ššššš šŖš°+= š. ššš = šš. š% šŖš°−= š. ššš = šš. š% š¶š¼ = 0.56 ± 1.96 ∗ √ The following is the minitab result Test and CI for One Proportion Sample 1 13. X 1120 N 2000 Sample p 0.560000 95% CI (0.537921, 0.581903) 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. CI = 95% = 1.96 = Z N = 50 X = 30 P = X/N = 0.6 š(1 − š) š¶š¼ = š ± š ∗ √ š 0.6(1 − 0.6) 50 šŖš° = š. š ± š. ššššš šŖš°+= š. ššš = šš. š% šŖš°−= š. ššš = šš. š% š¶š¼ = 0.6 ± 1.96 ∗ √ The following is the minitab result Test and CI for One Proportion Sample 1 14. X 30 N 50 Sample p 0.600000 95% CI (0.451794, 0.735922) Suppose that the number of wire-bonding defects per unit that occur in a semiconductor device is Poisson distributed with parameter lambda (Mu or variance) of 4. Then, the probability that a randomly selected semiconductor device will contain 2 or fewer wire-bonding defects is: λ=4 x=2 John M Awbrey Page 9 3/15/2016 š −š šš„ p(X = x) = š„! š −4 42 p(X = x) = 2! p(X = x) = 0.14652511 14.65 % The following is the minitab result Probability Density Function Poisson with mean = 4 x 2 P( X = x ) 0.146525 15. List and explain Deming’s 7 deadly diseases. I. Lack of constancy of purpose – this relates to Demings 14 points and ensures stakeholders that the business will grow II. Too much emphasis on short term profits – this commonly involves lowered quality which hurts the business long term III. Performance evaluation - Encourages short term performance by focusing on performance, employees can be left unhappy and actually perform worse. IV. Job hoping – managers who do not spend a long in a company and are constantly thinking about their next career move rather than their current work. V. Managing by visible figures alone – much of what makes a business successful is unknowable and managing based only on known facts can be a detriment. VI. Excessive medical expenses – Health care is important but extravagant spending on employees is unnecessary and costly. VII. Liability and excessive damage awards – minimize cost by reducing lawyer needs and relying on government intervention in large scale issues. 16. Explain who, when, and why six sigma was developed. What is the focus of six sigma? Motorola developed six sigma to meet the customer needs of quality on a level where defects are extremely unlikely. The old three sigma quality performance only offered results up to parts per thousand, with six sigma they can now find a low number of defects per million (almost 1). This is necessary for such large scale production. Especially when producing assemblies from parts built in many different plants, three sigma is just not acceptable enough for a final product. John M Awbrey Page 10 3/15/2016 17. Explain the DMAIC process and its relevance to quality. Define, Measure, Analyze, Improve, Control. First you define the problem to be tested, then measure the results of the process. The results are analyzed and possible methods for improvement are made. The last step is to setup a plan for continuing to control the improvement. This is used in quality as a standard process for improving a process. 18. What is HISTOGRAM and why it is being used? Histograms are a representation of data into cells, intervals, or bins. This is a useful way to quickly note patterns and get a general idea about the distribution of the data. Commonly, they will have the bellcurve of the data placed over them to accentuate the results. 19. Define Probability Distribution. What is the difference between discrete and continuous distributions? Provide Examples. Probability Distribution – the relationship of a variable with the probability of that variable taking on a certain value. Discrete distributions are used for counts and Bernoulli trials, such as a binomial or geometric distribution. A Continuous distribution is commonly used for measurements and can range from - to . These are used for distributions such as chi-square or normal distributions. 20. Define Bernoulli trials and Poisson distributions and explain their uses in Quality. Give example. Bernoulli trials are simple pass-fail tests of a sample taken from a population, such as the number of computers that work in the computer lab. A Poisson distribution is used for when there are multiple possible results of a Bernoulli trial, such as a part having an average number of defects, or an average number of events happening at a particular time. Bernoulli trials are useful for finding simple pass-fail results of a sample taken from a population of parts. Poisson distributions are useful for predicting the possible number of events given the previous averages of that event occurring, such as the number of defects within a part when an average number of defects are known.