LSSBB - Exam 1 Exam Questions and Answers

5 principles of Lean - ANSWER Value, Value Stream, Flow, Pull, Perfection VVsFPP Multi-variate analysis requires X and Y be: - ANSWER X - discrete Y - continuous degree of freedom (df) - ANSWER (sum of ...

5 principles of Lean - ANSWER Value, Value Stream, Flow, Pull, Perfection VVsFPP Multi-variate analysis requires X and Y be: - ANSWER X - discrete Y - continuous degree of freedom (df) - ANSWER (sum of samples) - (number of samples) Use non-parametric tests when: - ANSWER -non-normal data -sample too small for normality of avg -distribution not known -nominal / ordinal scaled data Mann-Whitney test used to: - ANSWER Compare 2 sample medians. Same as 2-sample t-test binomial logistic regression - ANSWER observed outcome of dependent varible only has 2 types, "0" and "1" After control limits are calculated, is there a need for revision of CLs? - ANSWER Yes. if reduction in variation / process shift. To avoid false special cause detection. Binomial distribution - ANSWER discrete. Not continuous. Same probability of success for each outcome. Sigma level - ANSWER measures process capability. measures how process performs against requirements. reps # of standard deviations between center and specification limit. P-charts based on: - ANSWER binomial distribution P-charts used for: - ANSWER tracking proportion or % defectives only 2 options: pass/fail; accept/reject Revised FMEA prepared in what phase: - ANSWER Control Phase Used as monitoring plan. Reassessed for out-of-control changes. Discrete data - ANSWER number by counting; no decimals. ex. items/persons Continuous data - ANSWER measured on a continuum; has decimal subdivisions Multi-vari chart used to: - ANSWER analyze effects of inputs on outputs horizontal scale of multi-vari chart = - ANSWER work shift, machine / material type, noise / uncontrolled factors Unequal variance due to: - ANSWER - extreme tails - outliers - multiple modes sampling distributions is aka: - ANSWER control charts 1. both plotted on sample data 2. show variation in sample data Effective LSS must understand difference between: - ANSWER practical & statistical significant practical difference / significance: - ANSWER difference of practical value statistical difference / significance: - ANSWER difference between actual difference and possible difference type 2 error occurs when: - ANSWER fails to reject the null (null is not rejected) ...when hypothesis is false (...when alt hypothesis is true) What does "s" symbolize in X-bar and S charts? - ANSWER process standard deviation what does S charts and R charts measure? - ANSWER subgroup variability What does S charts and R charts use? - ANSWER S chart uses - standard deviation R chart uses - range values Example of prevention cost: - ANSWER training what type of cost is quality audit? - ANSWER appraisal cost what type of cost is time value of money? - ANSWER hidden cost what type of cost is late delivery? - ANSWER hidden cost In VSM, triangle with "I" inside = - ANSWER exchange of inventory Where to add inventory count? - ANSWER below triangle icon What indicates out of control process? - ANSWER -one point outside UCL / LCL -8+ points on one side of center common cause variation - ANSWER inherent variation not easy to detect coefficient of determination - ANSWER - denoted by R^2 - proportion of variance in dependent, predictable from independent variable Mode is: - ANSWER most frequent occurring value in data set 1. 100 passed; 84 good (16 bad) 2. 110 passed; 82 good (28 bad) 3. 138 passed; 126 good (12 bad) Calculate RTY: - ANSWER RTY: (84/100) = 84% (82/110) = 75% (126/138) = 91% 84 x 75 x 91 = 57% Process capability index: - ANSWER uses process variability & specification limits to see if process is "capable" ability of process to produce output within spec limits 3 types of variation in sampling plan: - ANSWER within between temporal temporal variation: - ANSWER variation over time shift/day/week kaizen - ANSWER means change for better continuous improvement kanban - ANSWER means "card" used to control flow Poka-yoke - ANSWER mistake proofing Prod line A = 5000 units / hour Prod line B = 10,000 units / hour Prod line B 2x faster than A Example of: - ANSWER Ratio Scaled data Ratio scaled data - ANSWER can be ranked 2 true/false 1 multiple choice (4 choices) What is probability that all 3 are correct? - ANSWER 1/16 50% x 50% x 25% 95% confidence interval of students that play sports is 35% plus / minus 5% what is the 95% confidence interval: - ANSWER 30% - 40% 35 - 5 = 30 35 + 5 = 40 Test score: 190 test mean: 150 standard deviation: 25 what is z-score? - ANSWER z-score: (x-mean)/sd (190 - 150)/25 40/25 = 1.6 In order to determine statistical significance between mean of 2 distributions, you need: - ANSWER -test-statistics -confidence intervals -p-values Sampling method is biased if it: - ANSWER favors some outcomes over others Bias in sampling is an error due to: - ANSWER lack of independence systematic sampling If the control plan has a deviation, what does the control plan need to have to correct it: - ANSWER Reaction plan 1 sample t-test - ANSWER compares mean of a sample to a known target mean F-test - ANSWER Used to compare two variances Stratification - ANSWER points clustering around center line. lack of variability. Cause of stratification: - ANSWER incorrect control limits. Multi-Vari Chart - ANSWER screen inputs to see impact on outputs. Stability problem in measurement system means: - ANSWER lack of consistency over time. statistical difference - ANSWER change required between true difference and one that could occur by chance. Fish-bone diagram classifications: - ANSWER -controllable -procedural -noise ANOVA used to: - ANSWER -relationship between RESPONSE variable and INDEPENDENT variable -difference between MEANS In VSM, line with a zig-zag in middle: - ANSWER electronic flow symbol internet, elec data, etc. Created quality trilogy - ANSWER Juran Quality Trilogy (Juran Trilogy) - ANSWER reduce CoPQ by planning quality in process Contingency table - ANSWER AKA crosstab 2-way relationship between several variables 78 defects 10,000 units calculate DPU - ANSWER DPU = defects / total units 78 / 10,000 = .78 / 100 = 0.78% In VSM, supplier symbol placed: - ANSWER upper left corner In VSM, customer symbol placed: - ANSWER upper right corner In VSM, are customer / supplier symbols same or different? - ANSWER In VSM, customer and supplier symbols are same - placement is different. Correlation - ANSWER relationship strength between random variables regression - ANSWER mathematical relationship between two variables Gage R&R used to: - ANSWER see variation attributed to operator Wilcoxon sign test: - ANSWER compare mediam scores of 2 dependent samples Poisson distrbution - ANSWER discrete count over a constant space overproduction - ANSWER producing more that needed / customer demanded 1 of 8 types of waste I-MR chart - ANSWER plots individual observations on 1 chart & range of individual observations on another chart -shows process level and variation -detects special causes type 1 error - ANSWER rejection of true null hypothesis (false positive) type 2 error - ANSWER fails to reject a false null hypothesis (false negative) If r > 0.8 - ANSWER relationship practically significant If r < 0.2 - ANSWER relationship is not practically significant