Final Examination Thursday, April 30, 4:00 – 7:00 Location: here, Hanes 120 Suggested Study Strategy: Rework HW Out of Class Review Session? No, personal Q-A much better use of time Thus, instead offer extended Office Hours
Final Examination Thursday, April 30, 4:00 – 7:00 Location: here, Hanes 120 Suggested Study Strategy: Rework HW Out of Class Review Session? No, personal Q-A much better use of time Thus, instead offer extended Office Hours Bring with you, to exam: Single (8.5" x 11") sheet of formulas Front & Back OK
Final Examination Extended Office Hours Monday, April 27, 8:00 – 11:00 Tuesday, April 28, 12:00 – 2:30 Wednesday, April 29, 1:00 – 5:00 Thursday, April 30, 8:00 – 1:00
Last Time Unmatched 2 Sample Hypothesis Testing Linear Regression Fit lines to scatterplots Least squares fit Excel functions Diagnostic: Residual Plot Prediction
Review Slippery Issues Major Confusion:
Review Slippery Issues Major Confusion: Population Quantities
Review Slippery Issues Major Confusion: Population Quantities
Review Slippery Issues Major Confusion: Population Quantities
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Called Parameters
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Called Parameters Called Statistics
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Unknown
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Unknown, Goal is to estimate
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Unknown, Goal is to estimate, Use to fix ideas
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Unknown, Goal is to estimate, Use to fix ideas Get from data
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Unknown, Goal is to estimate, Use to fix ideas Get from data, Called “estimates”
Review Slippery Issues Major Confusion: Population Quantities vs. Sample Quantities Unknown, Goal is to estimate, Use to fix ideas Get from data, Called “estimates”, Know these
Levels of Probability Simple Events
Levels of Probability Simple Events Big Rules of Prob
Levels of Probability Simple Events Big Rules of Prob (Not, And, Or)
Levels of Probability Simple Events Big Rules of Prob (Not, And, Or) Bayes Rule
Levels of Probability Simple Events Distributions Big Rules of Prob (Not, And, Or) Bayes Rule Distributions
Levels of Probability Simple Events Distributions (in general) Big Rules of Prob (Not, And, Or) Bayes Rule Distributions (in general)
Levels of Probability Simple Events Distributions (in general) Big Rules of Prob (Not, And, Or) Bayes Rule Distributions (in general) Defined by Tables
Levels of Probability Simple Events Distributions (in general) Big Rules of Prob (Not, And, Or) Bayes Rule Distributions (in general) Defined by Tables Summary of discrete probs
Levels of Probability Simple Events Distributions (in general) Big Rules of Prob (Not, And, Or) Bayes Rule Distributions (in general) Defined by Tables Summary of discrete probs Get probs by summing
Levels of Probability Simple Events Distributions (in general) Big Rules of Prob (Not, And, Or) Bayes Rule Distributions (in general) Defined by Tables Summary of discrete probs Get probs by summing Uniform
Levels of Probability Simple Events Distributions (in general) Big Rules of Prob (Not, And, Or) Bayes Rule Distributions (in general) Defined by Tables Summary of discrete probs Get probs by summing Uniform Get probs by finding areas
Levels of Probability Distributions (in general)
Levels of Probability Distributions (in general) Named (& Useful) Distributions
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts Compute with BINOMDIST & Normal Approx.
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts Compute with BINOMDIST & Normal Approx. Normal
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts Compute with BINOMDIST & Normal Approx. Normal Continuous distribution of Averages
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts Compute with BINOMDIST & Normal Approx. Normal Continuous distribution of Averages Compute with NORMDIST & NORMINV
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts Compute with BINOMDIST & Normal Approx. Normal Continuous distribution of Averages Compute with NORMDIST & NORMINV T
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts Compute with BINOMDIST & Normal Approx. Normal Continuous distribution of Averages Compute with NORMDIST & NORMINV T Similar to Normal, for estimated s.d.
Levels of Probability Distributions (in general) Named (& Useful) Distributions Binomial Discrete distribution of Counts Compute with BINOMDIST & Normal Approx. Normal Continuous distribution of Averages Compute with NORMDIST & NORMINV T Similar to Normal, for estimated s.d. Compute with TDIST & TINV
Build Problem Solving Skills Decisions you need to make
Build Problem Solving Skills Decisions you need to make While taking Final Exam
Build Problem Solving Skills Decisions you need to make While taking Final Exam When faced with a word problem
Build Problem Solving Skills Decisions you need to make While taking Final Exam When faced with a word problem Key to deciding on approach
Build Problem Solving Skills Decisions you need to make While taking Final Exam When faced with a word problem Key to deciding on approach (e.g. knowing which formula to use)
Review Decisions Needed Main Challenge
Review Decisions Needed Main Challenge: Word problems on statistical inference
Review Decisions Needed Main Challenge: Word problems on statistical inference Choices to keep in mind
Review Decisions Needed Main Challenge: Word problems on statistical inference Choices to keep in mind: Big picture
Review Decisions Needed Main Challenge: Word problems on statistical inference Choices to keep in mind: Big picture: Single Sample
Review Decisions Needed Main Challenge: Word problems on statistical inference Choices to keep in mind: Big picture: Single Sample Two Samples
Review Decisions Needed Main Challenge: Word problems on statistical inference Choices to keep in mind: Big picture: Single Sample Two Samples Regression
Review Decisions Needed Probability model
Review Decisions Needed Probability model: Proportions
Review Decisions Needed Probability model: Proportions – Counts
Review Decisions Needed Probability model: Proportions – Counts (p based)
Review Decisions Needed Probability model: Proportions – Counts (p based) Normal Means
Review Decisions Needed Probability model: Proportions – Counts (p based) Normal Means – Measurements
Review Decisions Needed Probability model: Proportions – Counts (p based) Normal Means – Measurements (μ based)
Review Decisions Needed Probability model: Proportions
Review Decisions Needed Probability model: Proportions – Counts (p based)
Review Decisions Needed Probability model: Proportions – Counts (p based) Best Guess
Review Decisions Needed Probability model: Proportions – Counts (p based) Best Guess Conservative
Review Decisions Needed Probability model: Proportions – Counts (p based) Best Guess Conservative BINOMDIST
Review Decisions Needed Probability model: Proportions – Counts (p based) Best Guess Conservative BINOMDIST Normal Approx to Binomial
Review Decisions Needed Probability model: Proportions – Counts (p based) Best Guess Conservative BINOMDIST Normal Approx to Binomial (used usually for Hypo tests, etc.)
Review Decisions Needed Probability model: b. Normal Means (mu based)
Review Decisions Needed Probability model: b. Normal Means (mu based) Sigma known
Review Decisions Needed Probability model: b. Normal Means (mu based) Sigma known – NORMDIST & NORMINV
Review Decisions Needed Probability model: b. Normal Means (mu based) Sigma known – NORMDIST & NORMINV Sigma unknown
Review Decisions Needed Probability model: b. Normal Means (mu based) Sigma known – NORMDIST & NORMINV Sigma unknown – TDIST & TINV
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob Prob → Cutoff
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob Prob → Cutoff Counts, Prop’ns
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob Prob → Cutoff Counts, Prop’ns BINOMDIST ???
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob Prob → Cutoff Counts, Prop’ns BINOMDIST ??? Meas. σ known
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob Prob → Cutoff Counts, Prop’ns BINOMDIST ??? Meas. σ known NORMDIST NORMINV
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob Prob → Cutoff Counts, Prop’ns BINOMDIST ??? Meas. σ known NORMDIST NORMINV Meas. σ unkno’n
Review Decisions Needed Probability model: (Keeping Excel functions straight) Cutoff → Prob Prob → Cutoff Counts, Prop’ns BINOMDIST ??? Meas. σ known NORMDIST NORMINV Meas. σ unkno’n TDIST TINV
Review Decisions Needed Probability model: (Keeping Excel functions straight)
Review Decisions Needed Probability model: (Keeping Excel functions straight) Recall horrible Excel Organizations
Review Decisions Needed Probability model: (Keeping Excel functions straight) Recall horrible Excel Organizations Different functions work differently
Review Decisions Needed Probability model: (Keeping Excel functions straight) Recall horrible Excel Organizations Different functions work differently Indicate these on formula sheet…
Review Decisions Needed Probability model: (Keeping Excel functions straight) What about ??? (in above table)
Review Decisions Needed Probability model: (Keeping Excel functions straight) What about ???: There is no BINOMINV
Review Decisions Needed Probability model: (Keeping Excel functions straight) What about ???: There is no BINOMINV Since tricky to invert discrete prob’s
Review Decisions Needed Probability model: (Keeping Excel functions straight) What about ???: There is no BINOMINV Since tricky to invert discrete prob’s Have to use Normal Approx to Binomial
Review Decisions Needed 3. Inference Type
Review Decisions Needed 3. Inference Type: Confidence Interval
Review Decisions Needed 3. Inference Type: Confidence Interval Choice of Sample Size
Review Decisions Needed 3. Inference Type: Confidence Interval Choice of Sample Size Hypothesis Testing
Review Decisions Needed 3. Inference Type: Confidence Interval Choice of Sample Size Hypothesis Testing (each has its set of formulas…)
Review Decisions Needed 3. Inference Type: Confidence Interval
Review Decisions Needed 3. Inference Type: Confidence Interval Binomial type: Best guess, NORMINV
Review Decisions Needed 3. Inference Type: Confidence Interval Binomial type: Best guess, NORMINV Binomial type: Conservative, NORMINV
Review Decisions Needed 3. Inference Type: Confidence Interval Binomial type: Best guess, NORMINV Binomial type: Conservative, NORMINV Normal, σ known: NORMINV or CONFIDENCE
Review Decisions Needed 3. Inference Type: Confidence Interval Binomial type: Best guess, NORMINV Binomial type: Conservative, NORMINV Normal, σ known: NORMINV or CONFIDENCE Normal, σ unknown: TINV
Review Decisions Needed 3. Inference Type: Confidence Interval Binomial type: Best guess, NORMINV Binomial type: Conservative, NORMINV Normal, σ known: NORMINV or CONFIDENCE Normal, σ unknown: TINV (each has its set of formulas…)
Review Decisions Needed 3. Inference Type: Choice of Sample Size Binomial type: Best guess, NORMINV Binomial type: Conservative, NORMINV Normal, σ known: NORMINV Normal, σ unknown: TINV (each has its set of formulas…)
Review Decisions Needed 3. Inference Type: Hypothesis Testing – P-values Binomial type: NORMDIST (or BINOMDIST)
Review Decisions Needed 3. Inference Type: Hypothesis Testing – P-values Binomial type: NORMDIST (or BINOMDIST) Normal, σ known: NORMDIST
Review Decisions Needed 3. Inference Type: Hypothesis Testing – P-values Binomial type: NORMDIST (or BINOMDIST) Normal, σ known: NORMDIST Normal, σ unknown: TDIST
Review Decisions Needed 3. Inference Type: Hypothesis Testing – P-values Binomial type: NORMDIST (or BINOMDIST) Normal, σ known: NORMDIST Normal, σ unknown: TDIST Variation, σ known: Z-stat
Review Decisions Needed 3. Inference Type: Hypothesis Testing – P-values Binomial type: NORMDIST (or BINOMDIST) Normal, σ known: NORMDIST Normal, σ unknown: TDIST Variation, σ known: Z-stat Variation, σ unknown: t-stat
Review Decisions Needed 3. Inference Type: Hypothesis Testing – P-values Binomial type: NORMDIST (or BINOMDIST) Normal, σ known: NORMDIST Normal, σ unknown: TDIST Variation, σ known: Z-stat Variation, σ unknown: t-stat (each has its set of formulas…)
Review Decisions Needed Summary of decisions
Review Decisions Needed Summary of decisions 1. Big picture
Review Decisions Needed Summary of decisions 1. Big picture: (Single - Two Samples – 2 Way Tab’s – Reg’n)
Review Decisions Needed Summary of decisions 1. Big picture: (Single - Two Samples – 2 Way Tab’s – Reg’n) 2. Probability model
Review Decisions Needed Summary of decisions 1. Big picture: (Single - Two Samples – 2 Way Tab’s – Reg’n) 2. Probability model: (Prop’ns (Counts) - Normal (Meas’ts))
Review Decisions Needed Summary of decisions 1. Big picture: (Single - Two Samples – 2 Way Tab’s – Reg’n) 2. Probability model: (Prop’ns (Counts) - Normal (Meas’ts)) 3. Inference Type
Review Decisions Needed Summary of decisions 1. Big picture: (Single - Two Samples – 2 Way Tab’s – Reg’n) 2. Probability model: (Prop’ns (Counts) - Normal (Meas’ts)) 3. Inference Type: (Conf. Int. - Sample Size – Hypo Testing)
Practice Making Decisions Print all HW pages
Practice Making Decisions Print all HW pages Randomly choose page
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem Work that out
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem Work that out (make decisions…)
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem Work that out (make decisions…) Mark it off
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem Work that out (make decisions…) Mark it off Return & repeat
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem Work that out (make decisions…) Mark it off Return & repeat
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem Work that out (make decisions…) Mark it off Return & repeat Finish all correctly?
Practice Making Decisions Print all HW pages Randomly choose page Randomly choose problem Work that out (make decisions…) Mark it off Return & repeat Finish all correctly? An easy A in this course
And now for something completely different… Two issues
And now for something completely different… Two issues: What do professional statisticians think about EXCEL?
And now for something completely different… Two issues: What do professional statisticians think about EXCEL? Why are the EXCEL functions so poorly organized?
And now for something completely different… Professional Statisticians Dislike Excel
And now for something completely different… Professional Statisticians Dislike Excel: Very poor handling of numerics
And now for something completely different… Professional Statisticians Dislike Excel: Very poor handling of numerics Formerly: Unacceptable?!?
And now for something completely different… Professional Statisticians Dislike Excel: Very poor handling of numerics Formerly: Unacceptable?!? Jeff Simonoff Example: http://www.stern.nyu.edu/~jsimonof/classes/1305/pdf/excelreg.pdf
And now for something completely different… Professional Statisticians Dislike Excel: Very poor handling of numerics Formerly: Unacceptable?!? Jeff Simonoff Example: http://www.stern.nyu.edu/~jsimonof/classes/1305/pdf/excelreg.pdf (Problem with Earlier Versions of Excel)
And now for something completely different… Old Problem 1: Excel didn’t keep enough significant digits (relative to other software)
And now for something completely different… Old Problem 1: Excel didn’t keep enough significant digits (relative to other software) [single precision vs. double precision]
And now for something completely different… Problem 2: Excel doesn’t warn when troubles are encountered…
And now for something completely different… Problem 2: Excel doesn’t warn when troubles are encountered… All software has its limitation
And now for something completely different… Problem 2: Excel doesn’t warn when troubles are encountered… All software has its limitation But it is easy to provide warnings…
And now for something completely different… Problem 2: Excel doesn’t warn when troubles are encountered… All software has its limitation But it is easy to provide warnings… “Competent software does this…”
And now for something completely different… Why are the EXCEL functions so poorly organized?
And now for something completely different… Why are the EXCEL functions so poorly organized? E.g. NORMDIST uses left areas
And now for something completely different… Why are the EXCEL functions so poorly organized? E.g. NORMDIST uses left areas TDIST uses right or 2-sided areas
And now for something completely different… Why are the EXCEL functions so poorly organized? E.g. NORMDIST uses left areas TDIST uses right or 2-sided areas E.g. NORMINV uses left areas
And now for something completely different… Why are the EXCEL functions so poorly organized? E.g. NORMDIST uses left areas TDIST uses right or 2-sided areas E.g. NORMINV uses left areas TINV uses 2-sided areas
And now for something completely different… Why are the EXCEL functions so poorly organized?
And now for something completely different… Why are the EXCEL functions so poorly organized? Looks like programmer was handed a statistics text
And now for something completely different… Why are the EXCEL functions so poorly organized? Looks like programmer was handed a statistics text, and told “turn these into functions”…
And now for something completely different… Why are the EXCEL functions so poorly organized? Looks like programmer was handed a statistics text, and told “turn these into functions”… Problem: organization was good for table look ups, but looks clunky now…
And now for something completely different… Fun personal story:
And now for something completely different… Fun personal story: Colin Bell @ Microsoft heard about “complaints from statisticians on EXCEL”
And now for something completely different… Fun personal story: Colin Bell @ Microsoft heard about “complaints from statisticians on EXCEL” Decided to “try to fix these”
And now for something completely different… Fun personal story: Colin Bell @ Microsoft heard about “complaints from statisticians on EXCEL” Decided to “try to fix these” Contacted Jeff Simonoff about numerics
And now for something completely different… Fun personal story: Colin Bell @ Microsoft heard about “complaints from statisticians on EXCEL” Decided to “try to fix these” Contacted Jeff Simonoff about numerics Asked Jeff to work with him
And now for something completely different… Fun personal story: Colin Bell @ Microsoft heard about “complaints from statisticians on EXCEL” Decided to “try to fix these” Contacted Jeff Simonoff about numerics Asked Jeff to work with him Jeff refused, doesn’t like or use EXCEL
And now for something completely different… Fun personal story: Jeff told Colin about me
And now for something completely different… Fun personal story: Jeff told Colin about me Colin asked me
And now for something completely different… Fun personal story: Jeff told Colin about me Colin asked me I agreed about numerical problems
And now for something completely different… Fun personal story: Jeff told Colin about me Colin asked me I agreed about numerical problems, but said I had bigger objections about organization
And now for something completely different… Fun personal story: Jeff told Colin about me Colin asked me I agreed about numerical problems, but said I had bigger objections about organization Colin asked me to write these up
And now for something completely different… Fun personal story: I said I was too busy, but…
And now for something completely different… Fun personal story: I said I was too busy, but… I would teach (similar course) soon
And now for something completely different… Fun personal story: I said I was too busy, but… I would teach (similar course) soon. I offered to send an email
And now for something completely different… Fun personal story: I said I was too busy, but… I would teach (similar course) soon. I offered to send an email, every time I noted an organizational inconsistency
And now for something completely different… Fun personal story: I said I was too busy, but… I would teach (similar course) soon. I offered to send an email, every time I noted an organizational inconsistency Over the semester, I sent around 30 emails about all of these
And now for something completely different… Fun personal story: Colin agreed with each of the points made
And now for something completely different… Fun personal story: Colin agreed with each of the points made Colin approached the statistical people at Microsoft
And now for something completely different… Fun personal story: Colin agreed with each of the points made Colin approached the statistical people at Microsoft They agreed that organization could have been done better
And now for something completely different… Fun personal story: But for “backwards compatibility” reasons, refused to change anything
And now for something completely different… Fun personal story: But for “backwards compatibility” reasons, refused to change anything (even when Office 2007 came out…)
And now for something completely different… Fun personal story: But for “backwards compatibility” reasons, refused to change anything Colin apologetically archived all my emails…
And now for something completely different… How much should we worry:
And now for something completely different… How much should we worry: Organization is a pain, but you can live with it
And now for something completely different… How much should we worry: Organization is a pain, but you can live with it (OK to complain when you feel like it)
And now for something completely different… How much should we worry: Organization is a pain, but you can live with it (OK to complain when you feel like it) Usually (except for weird rounding) numerical issues don’t arise
And now for something completely different… How much should we worry: Organization is a pain, but you can live with it (OK to complain when you feel like it) Usually (except for weird rounding) numerical issues don’t arise, but need to be aware of potential!
Some Examples Attempt to illustrate how to avoid common mistakes
Some Examples Attempt to illustrate how to avoid common mistakes Guiding Principle:
Some Examples Attempt to illustrate how to avoid common mistakes Guiding Principle: (& useful color scheme)
Population Quantities Recall Main Framework Need to keep straight: Population Quantities vs. Sample Quantities Unknown, Goal is to estimate, Use to fix ideas Get from data, Called “estimates”, Know these
Hypothesis Testing E.g. A fast food chain currently brings in profits of $20,000 per store, per day
Hypothesis Testing E.g. A fast food chain currently brings in profits of $20,000 per store, per day. A new menu is proposed.
Hypothesis Testing E.g. A fast food chain currently brings in profits of $20,000 per store, per day. A new menu is proposed. Would it be more profitable?
Hypothesis Testing E.g. A fast food chain currently brings in profits of $20,000 per store, per day. A new menu is proposed. Would it be more profitable? Test: Have 10 stores
Hypothesis Testing E.g. A fast food chain currently brings in profits of $20,000 per store, per day. A new menu is proposed. Would it be more profitable? Test: Have 10 stores (randomly selected!)
Hypothesis Testing E.g. A fast food chain currently brings in profits of $20,000 per store, per day. A new menu is proposed. Would it be more profitable? Test: Have 10 stores (randomly selected!) try the new menu
Hypothesis Testing E.g. A fast food chain currently brings in profits of $20,000 per store, per day. A new menu is proposed. Would it be more profitable? Test: Have 10 stores (randomly selected!) try the new menu, let = average of their daily profits.
Hypothesis Testing Suppose observe:
Hypothesis Testing Suppose observe: ,
Hypothesis Testing Suppose observe: , based on
Hypothesis Testing Suppose observe: , based on Note
Hypothesis Testing Suppose observe: , based on Note , but is this conclusive?
Hypothesis Testing Suppose observe: , based on Note , but is this conclusive? or could this be due to natural sampling variation? (i.e. do we risk losing money from new menu?)
Hypothesis Testing E.g. Fast Food Menus: Test
Hypothesis Testing E.g. Fast Food Menus: Test
Hypothesis Testing E.g. Fast Food Menus: Test Using
Hypothesis Testing E.g. Fast Food Menus: Test Using
Hypothesis Testing E.g. Fast Food Menus: Test Using P-value = P{what saw or m.c.| H0 & HA bd’ry}
Hypothesis Testing E.g. Fast Food Menus: Test Using P-value = P{what saw or m.c.| H0 & HA bd’ry}
Hypothesis Testing E.g. Fast Food Menus: Test Using P-value = P{what saw or m.c.| H0 & HA bd’ry}
(guides where to put $21k & $20k) Hypothesis Testing E.g. Fast Food Menus: Test Using P-value = P{what saw or m.c.| H0 & HA bd’ry} (guides where to put $21k & $20k)
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Hypothesis Testing P-value = P{what saw or or m.c.| H0 & HA bd’ry}
Consider Variations Look carefully at how problems can be twiddled, to get opposite answer
Hypothesis Testing CAUTION: Read problem carefully to distinguish between: One-sided Hypotheses
Hypothesis Testing CAUTION: Read problem carefully to distinguish between: One-sided Hypotheses - like:
Hypothesis Testing CAUTION: Read problem carefully to distinguish between: One-sided Hypotheses - like: Two-sided Hypotheses
Hypothesis Testing CAUTION: Read problem carefully to distinguish between: One-sided Hypotheses - like: Two-sided Hypotheses - like:
Hypothesis Testing Hints: Use 1-sided when see words like
Hypothesis Testing Hints: Use 1-sided when see words like: Smaller Greater In excess of
Hypothesis Testing Hints: Use 1-sided when see words like: Smaller Greater In excess of Use 2-sided when see words like:
Hypothesis Testing Hints: Use 1-sided when see words like: Smaller Greater In excess of Use 2-sided when see words like: Equal Different
Hypothesis Testing Hints: Use 1-sided when see words like: Smaller Greater In excess of Use 2-sided when see words like: Equal Different Always write down H0 and HA
Hypothesis Testing Hints: Use 1-sided when see words like: Smaller Greater In excess of Use 2-sided when see words like: Equal Different Always write down H0 and HA Since then easy to label “more conclusive”
Hypothesis Testing Hints: Use 1-sided when see words like: Smaller Greater In excess of Use 2-sided when see words like: Equal Different Always write down H0 and HA Since then easy to label “more conclusive” And get partial credit….
Hypothesis Testing E.g. Old text book problem 6.34
Hypothesis Testing E.g. Old text book problem 6.34: In each of the following situations, a significance test for a population mean, is called for.
Hypothesis Testing E.g. Old text book problem 6.34: In each of the following situations, a significance test for a population mean, is called for. State the null hypothesis, H0
Hypothesis Testing E.g. Old text book problem 6.34: In each of the following situations, a significance test for a population mean, is called for. State the null hypothesis, H0 and the alternative hypothesis, HA in each case….
Hypothesis Testing E.g. 6.34a An experiment is designed to measure the effect of a high soy diet on bone density of rats. Let = average bone density of high soy rats = average bone density of ordinary rats (since no question of “bigger” or “smaller”)
Variation E.g. 6.34a An experiment is designed to see if a high soy diet increases bone density of rats. Let = average bone density of high soy rats = average bone density of ordinary rats (since “bigger” is goal)
Hypothesis Testing E.g. 6.34b Student newspaper changed its format. In a random sample of readers, ask opinions on scale of -2 = “new format much worse”, -1 = “new format somewhat worse”, 0 = “about same”, +1 = “new a somewhat better”, +2 = “new much better”. Let = average opinion score
Hypothesis Testing E.g. 6.34b (cont.) No reason to choose one over other, so do two sided. Note: Use one sided if question is of form: “is the new format better?”
Hypothesis Testing E.g. 6.34c The examinations in a large history class are scaled after grading so that the mean score is 75. A teaching assistant thinks that his students have a higher average score than the class as a whole. His students can be considered as a sample from the population of all students he might teach, so he compares their score with 75. = average score for all students of this TA
Variation E.g. 6.34c The examinations in a large history class are scaled after grading so that the mean score is 75. A teaching assistant thinks that his students have a different average score from the class as a whole. His students can be considered as a sample from the population of all students he might teach, so he compares their score with 75. = average score for all students of this TA
Hypothesis Testing E.g. Textbook problem 6.36 Translate each of the following research questions into appropriate and Be sure to identify the parameters in each hypothesis (generally useful, so already did this above).
Hypothesis Testing E.g. 6.36a A researcher randomly divides 6-th graders into 2 groups for PE Class, and teached volleyball skills to both. She encourages Group A, but acts cool towards Group B. She hopes that encouragement will result in a higher mean test for group A. Let = mean test score for Group A = mean test score for Group B
Hypothesis Testing E.g. 6.36a Recall: Set up point to be proven as HA
Variation E.g. 6.36a A researcher randomly divides 6-th graders into 2 groups for PE Class, and teached volleyball skills to both. She encourages Group A, but acts cool towards Group B. She wonders whether encouragement will result in a different mean test for group A. Let = mean test score for Group A = mean test score for Group B
Variation E.g. 6.36a Recall: Set up point to be proven as HA
Hypothesis Testing E.g. 6.36b Researcher believes there is a positive correlation between GPA and esteem for students. To test this, she gathers GPA and esteem score data at a university. Let = correlation between GPS & esteem
Variation E.g. 6.36b Researcher investigates the potential correlation between GPA and esteem for students. To test this, she gathers GPA and esteem score data at a university. Let = correlation between GPS & esteem
Hypothesis Testing E.g. 6.36c A sociologist asks a sample of students which subject they like best. She suspects a higher percentage of females, than males, will name English. Let: = prop’n of Females preferring English = prop’n of Males preferring English
Variation E.g. 6.36c A sociologist asks a sample of students which subject they like best. Is there a difference between the percentage of females & males, that name English. Let: = prop’n of Females preferring English = prop’n of Males preferring English
And Now for Something Completely Different Etymology of: “And now for something completely different”
And Now for Something Completely Different Etymology of: “And now for something completely different” Anybody heard of this before? (really 2 questions…)
And Now for Something Completely Different Etymology of: “And now for something completely different” Anybody heard of this before? (really 2 questions…)
And Now for Something Completely Different Etymology of: “And now for something completely different” Anybody heard of this before? (really 2 questions…)
And Now for Something Completely Different What is “etymology”?
And Now for Something Completely Different What is “etymology”? Google responses to: define: etymology
And Now for Something Completely Different What is “etymology”? Google responses to: define: etymology The history of words; the study of the history of words. csmp.ucop.edu/crlp/resources/glossary.html
And Now for Something Completely Different What is “etymology”? Google responses to: define: etymology The history of words; the study of the history of words. csmp.ucop.edu/crlp/resources/glossary.html The history of a word shown by tracing its development from another language. www.animalinfo.org/glosse.htm
And Now for Something Completely Different What is “etymology”? Etymology is derived from the Greek word e/)tymon(etymon) meaning "a sense" and logo/j(logos) meaning "word." Etymology is the study of the original meaning and development of a word tracing its meaning back as far as possible. www.two-age.org/glossary.htm
And Now for Something Completely Different Google response to: define: and now for something completely different
And Now for Something Completely Different Google response to: define: and now for something completely different And Now For Something Completely Different is a film spinoff from the television comedy series Monty Python's Flying Circus.
And Now for Something Completely Different Google response to: define: and now for something completely different And Now For Something Completely Different is a film spinoff from the television comedy series Monty Python's Flying Circus. The title originated as a catchphrase in the TV show. Many Python fans feel that it excellently describes the nonsensical, non sequitur feel of the program. en.wikipedia.org/wiki/And_Now_For_Something_Completely_Different
And Now for Something Completely Different Google Search for: “And now for something completely different” Gives more than 100 results…. A perhaps interesting one: http://www.mwscomp.com/mpfc/mpfc.html
And Now for Something Completely Different Google Search for: “Stor 155 and now for something completely different” Gives: [PPT] Slide 1 File Format: Microsoft Powerpoint - View as HTML http://stat-or.unc.edu/webspace/postscript/marron/Teaching/stor155-2007/ ... And Now for Something Completely Different. P: Dead bugs on windshield. ... stat-or.unc.edu/webspace/postscript/marron/Teaching/stor155-2007/Stor155-07-01-30.ppt - Similar pages