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... . . . . . . . . . . . . . 9.5 Limitations and Common Misinterpretations of Hypothesis Testing . . . . . . . . . . 1 1 6 10 15 17 Stat 3011 Chapter 9 CHAPTER 9: HYPOTHESIS TESTS Motivating Example A diet pill company advertises that at least 75% of its customers lose 10 pounds or more within 2 weeks. You suspect the company of falsely advertising the beneﬁts of taking their pills. Suppose you take a sample of 100 product users and ﬁnd that only 5% have lost at least 10 pounds. Is this enough to prove your claim? What about if 72% had lost at least 10 pounds? Goal: 9.1 Elements of a Hypothesis Test 1. Assumptions 2. Hypotheses Each hypothesis test has two hypotheses about the population: Null Hypothesis (H0 ): Alternative Hypothesis (Ha ): 1 Stat 3011 Chapter 9 Diet Pill Example: Let p = true proportion of diet pill customers that lose at least 10 pounds. State the null and alternative hypotheses for the diet pill example. 3. Test Statistic Deﬁnition: Test Statistic A test statistic is a measure of how compatible the data is with the null hypothesis. The larger the test statistic, the less compatible the data is with the null hypothesis. Most test statistics we will see have the following form: What does a large value of |T | reﬂect? NOTE: 2 Stat 3011 Chapter 9 4. p-value The p-value helps us to interpret the test statistic. Deﬁnition: p-value Assume H0 is true. Then the p-value is the probability that the test statistic......

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...and the regularity with which payments have been made. A bad and irregular payment history causes the score to drop down. * Amounts Owed (30%): The total amount of debts owed to other lenders is also an important consideration in the score calculation. The standard equation is, more the amounts owed, less is the credit score. Hence keep the credit history and current liabilities to the bare minimum. * Length of Credit History (15%): The length of the credit history is also considered. Rule of the thumb is that longer the history, lesser is the score. Thus avoid unnecessary borrowings and keep them to the bare minimum. * New Credit (10%): New credit consists of the newly borrowed loans or newly taken up credit cards. Keeping it small always helps, as the lesser the new credit, the better is the credit score. * Types of Credit Used (10%): The types of credit such as credit cards, types of loans and other credits such as buy now pay later, constitute the score. This proportion is applied to get a number on the credit core rating sale, which usually extends from 500 to 850 or in some cases, 300 to 750. This credit score scale may differ as per the company and FICO program. Any drastic or negative change in the aforementioned aspects is going to bring down your score. The exact opposite is applicable for scores, positive things such as of you pay off a loan properly, then the score increases. Apart from these constituent factors other incidents also tend to have an impact on the......

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...what is generics in jdk1.5? | | |Answer |Hi, | | |# 1 | | | | |Generics is Template support added in JDK1.5 where in we can maintain templates of object with particular type and | | | |also this object is restricted to accept type other than specified one at code time. | | | |This help reducing runtime exception and also we can create predefined well formed templates of Type. | | | | | | | |Best Example. | | | | | | | |http://java.sun.com/j2se/1.5.0/docs/relnotes/features.html#generics | | | | | | | |Code written to use the generics feature should not be a lot slower or a lot more memory-intensive than non-generic | | | ...

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...have actively demonstrated an interest in security. This isn’t a random sample of all the people in the country who are ostensibly responsible for the security of their networks. It’s a sample of those with sufficient interest in security to be CSI members or to have attended a CSI paid event. CSI caters to security professionals on the front lines, so it goes without saying that the respondents to this survey come from a community that is actively working to improve security. This pool, in short, doesn’t stand in for the organizations in the United States that are simply not paying attention to security (and there are, unfortunately, all too many such organizations). Second, respondents fill out the questionnaire voluntarily, without any help from us. So one must reckon with the possibility that the respondents are self-selected based on some salient quality. For example, are they more likely to respond to the survey if they have more data or more accurate data at hand; and if so, is that indicative of a better overall security program? Are they more likely to respond if they have or have not experienced a significant security incident? All responses are submitted anonymously, which is done to encourage candor, but which also means that it is impossible to directly chase after those who have self-selected not to fill out the form. This anonymity furthermore introduces a limitation in comparing data year over year, because of the possibility that entirely different people are......

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...STAT 302 – Statistical Methods Lecture 8 Dr. Avishek Chakraborty Visiting Assistant Professor Department of Statistics Texas A&M University Using sample data to draw a conclusion about a population • Statistical inference provides methods for drawing conclusions about a population from sample data. • Two key methods of statistical inference: o o Confidence intervals Hypothesis tests (a.k.a., tests of significance) Hypothesis Testing: Evaluating the effectiveness of new machinery at the Bloggs Chemical Plant • Before the installation of new machinery, long historical records revealed that the daily yield of fertilizer produced by the Bloggs Chemical Plant had a mean μ = 880 tons and a standard deviation σ = 21 tons. Some new machinery is being evaluated with the aim of increasing the daily mean yield without changing the population standard deviation σ. Hypothesis Testing: Evaluating the effectiveness of new machinery at the Bloggs Chemical Plant Null hypotheses • The claim tested by a statistical test is called the null hypothesis. The test is designed to assess the strength of the evidence against the null hypothesis. Usually the null hypothesis is a statement of “no effect” or “no difference”, that is, a statement of the status quo. Alternative hypotheses • The claim about the population that we are trying to find evidence for is the alternative hypothesis. The alternative hypothesis is one-sided if it states that a parameter is larger than or...

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...printout given above), Explain (0, (1, also provide the units of slope and y-intercept. Does (0, (1 make sense? d) Is there sufficient evidence to conclude that the model contributes information for predicting the Percentage of refund spent in 3-months? (State Hypothesis, and do the test.) e) Is there sufficient evidence to conclude, "As the family income increases than the Percentage of refund spent in 3-month decreases? (State Hypothesis, and do the test.) (Does it make sense to do this test? Explain) f) Calculate R-sq, what is the practical meaning of R-sq? g) Calculate the Standard error of Estimate, What is the practical meaning of S(? (Get the residual printouts – 5 points) In Minitab, Goto Stat>regression>regression, then follow the screen prints below to get the residual plots. [pic] [pic] And click ok h) State the regression Assumption 1 and test it using the residual plots. i) State the regression Assumption 2 and test it using the residual plots. j) State the regression Assumption 3 and test it using the residual plots. k) State the regression Assumption 4 and test it using the residual plots. l) Calculate R-sq(adjusted). m) Find 95% Confidence Interval for (0 n) Find 95% Confidence Interval for (1 o) Explain the relationship between Confidence Interval and Hypothesis testing. p) What is an Outlier? Are there any outliers? q) What is an...

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... Grant & Judith Jordan www.founda4onsofstrategy.com Motivates and mobilises 12 6 What Is a Strategic Plan? Elements of a Firm’s Strategic Plan Its strategic vision, business mission, and core values Its strategic and financial objectives Its chosen strategy Vision Statement for UBS We are determined to be the best global financial services company. We focus on wealth and asset management, and on investment banking and securities businesses. We continually earn recognition and trust from clients, shareholders, and staff through our ability to anticipate, learn and shape our future. We share a common ambition to succeed by delivering quality in what we do. Our purpose is to help our clients make financial decisions with confidence. We use our resources to develop effective solutions and services for our clients. We foster a distinctive, meritocratic culture of ambition, performance and learning as this attracts, retains and develops the best talent for our company. By growing both our client and our talent franchises, we add sustainable value for our shareholders. Effective Elements Shortcomings • Focused • Feasible • Desirable • Not forward-looking • Bland or uninspiring • Hard to communicate 7 The Strategy-Making Hierarchy Corporate Strategy Multibusiness Strategy—how to gain synergies from managing a portfolio of businesses together rather than as separate businesses Two-Way Influence......

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...lecturer, Mr. Ian for his valuable advice and guidance. His willingness to motivate us contributes tremendously to this assignment. We also would like to thank him for showing some examples and samples that related to this assignment. Finally, an honorable mention goes to our families and friend for their understanding, support and encouragement on us in completing this assignment. Without the helps from any of them, we would face many difficulties while completing this assignment. Introduction Through in assignment, we can understand the importance of statistics in business activities and can learn how to present and describe data or information properly and clearly. Using statistics, we can make reliable forecasts about a business activity which can improve business process. From this assignment, we learn how to collect, analyze, and interpret data into useful information and draw conclusions about the students in the class using the information we collected. Furthermore, we can learn how to use Microsoft Excel application software to draw histogram, charts and graphs to help us in summarizing the relationship between the data collected. 7. Determine the following for the height data: a) Lower Quartile Position of Q1= 20+14 = 5.25 = 5 Q1= 163cm b) Upper Quartile Position of Q3= 15.75 = 16 Q3 = 173cm c) Interquartile Range IQR = Q3 - Q1 = 173cm – 163cm =......

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...NORTHEASTERN UNIVERSITY - GRADUATE SCHOOL OF BUSINESS ADMINISTRATION MGSC 6200: DATA ANALYSIS Spring, 2015 Instructor Information Name: Dr. Nizar Zaarour E-mail address: n.zaarour@neu.edu Office: 214 Hayden Hall Office hours: Monday and Wednesday: 12 – 2 PM and by appointment. Course Overview The objectives of this course are: (1) To provide you with an understanding of statistical methods and techniques and their usefulness in the decision-making process, (2) To expose you to the methods of descriptive and inferential statistics and how can be used to solve business problems, (3) To improve upon your data analysis and computer skills, (4) To help you develop the skills to recognize the appropriate statistical tool to analyze business problems, and (5) To provide you with the necessary tools for critical evaluation, correct interpretation, and presentation of the results of statistical analyses. Textbook and Software 1) Business Statistics: For Contemporary Decision Making, 7th Edition, by Ken Black, (Wiley). 2) Microsoft Excel. Course Organization The course web page is located in the Blackboard system at http://blackboard.neu.edu. Course materials and announcements will be posted on the course site. A Blackboard tutorial is available at http://www.discoveringblackboard.neu.edu. The textbook is quite easy to read and covers a lot of ground. However, some of the topics are not covered in depth. Class discussions, handouts, and my lecture notes will fill these......

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...use 0.75. Plotting the Binomial Probabilities 1. Create plots for the three binomial distributions above. Select Graph > Scatter Plot and Simple then for graph 1 set Y equal to ‘one fourth’ and X to ‘success’ by clicking on the variable name and using the “select” button below the list of variables. Do this two more times and for graph 2 set Y equal to ‘one half’ and X to ‘success’, and for graph 3 set Y equal to ‘three fourths’ and X to ‘success’. Paste those three scatter plots below. Calculating Descriptive Statistics Open the class survey results that were entered into the MINITAB worksheet. 2. Calculate descriptive statistics for the variable where students flipped a coin 10 times. Pull up Stat > Basic Statistics > Display Descriptive Statistics and set Variables: to the coin. The output will show up in your Session Window. Type the mean and the standard deviation here. Mean: 4.600 Standard deviation: 1.429 Short Answer Writing Assignment – Both the calculated binomial probabilities and the descriptive statistics from the class database will be used to answer the following questions. 3. List the probability value for each possibility in the binomial experiment that was calculated in MINITAB with the probability of a success being ½. (Complete sentence not......

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...endpoint values for a large market does developing the battery have a lower EMV than not developing the battery? Source ------------------------------------------------- Top of Form * Less than $1.2 million. * Greater than $1.2 million. * Greater than $0.75 million. * None of the above. 44. The manager of the Eris Shoe Company must decide whether or not to contract a controversial sports celebrity as its spokesperson. The new spokesperson's value to Eris depends heavily on consumers' perception of him. An initial decision analysis based on available data reveals that the expected monetary value of contracting the new spokesperson is $260,000. For $50,000 Eris can engage a market research firm that will help Eris learn more about how consumers might react to the celebrity. The EMV of buying this sample information (assuming it is free) for this decision is $300,000. The tree below summarizes Eris's decision. Based on EMV analysis, Eris's manager should: * Hire the research firm. * Not hire the research firm, but contract the new spokesperson. * Not hire the research firm and not contract the new spokesperson. * The answer cannot be determined from the information 7. 7. For a given set of data, the standard deviation measures: Source Top of Form * The difference between the mean and the data point farthest from the mean. * The difference between the mean and the data point nearest to the......

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...It’s probably unbelievable to you hearing this from me because nowadays almost everybody watches TV and everyone is aware of what is in the news. While looking up about “Gold Rush” I noticed it wasn’t a new series, it had actually been released since 2010 and now it is composed of 6 episodes. I think I should start watching TV since I felt I have been missing tons of stuff. In addition to this program I think it is essential to say that the network involved is “Disc”. I also went to look for most popular music and of course the first thing I saw was Justin Bieber with his song “Be yourself”, I usually listen to this song almost everyday because it is actually popular, but after knowing it is in the first place of ranking list I couldn’t help the craving of knowing how many reproductions it has on Youtube. Well it has about 247,768,905 reproductions in just 3 months, isn’t that crazy? I guess people are not surprised anymore about Justin’s fame. Another topic that caught my attention was about the alcohol section; I went to the beer option and “Bud Light” came out to be the most popular beer with an amount of $440,275,922 in sells. I believe this beer must be really good or really cheap; two reasons for buying it. On the other hand I also looked for the most popular soda in the country and obviously it came out to be “Coca-Cola” with an amount of $258,474,509 in sells. This is not a surprise since Coca-Cola has always been the most popular soda worldwide. In the......

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...Chapter 9 Hypothesis Tests Solutions: 6. a. H0: μ ≤ 1 Ha: μ > 1 b. Claiming μ > 1 when it is not. This is the error of rejecting the product’s claim when the claim is true. Concluding μ ≤ 1 when it is not. In this case, we miss the fact that the product is not meeting its label specification. H0: μ ≤ 8000 Ha: μ > 8000 b. Research hypothesis to see if the plan increases average sales. The label claim or assumption. c. 7. a. Claiming μ > 8000 when the plan does not increase sales. A mistake could be implementing the plan when it does not help. Concluding μ ≤ 8000 when the plan really would increase sales. This could lead to not implementing a plan that would increase sales. z= x − μ0 = 26.4 − 25 6 / 40 = 1.48 c. 10. a. b. σ/ n Upper tail p-value is the area to the right of the test statistic Using normal table with z = 1.48: p-value = 1.0000 - .9306 = .0694 Using Excel: p-value = 1 - NORMSDIST(1.48) = .0694 c. d. p-value > .01, do not reject H0 Reject H0 if z ≥ 2.33 1.48 < 2.33, do not reject H0 11. a. b. z= x − μ0 σ/ n = 14.15 − 15 3 / 50 = −2.00 Because z < 0, p-value is two times the lower tail area Using normal table with z = -2.00: p-value = 2(.0228) = .0456 9-1 Chapter 9 Using Excel: p-value = 2*NORMSDIST(-2.00) = .0456 c. d. p-value ≤ .05, reject H0 Reject H0 if z ≤ -1.96 or z ≥ 1.96 -2.00 ≤ -1.96, reject H0 15. a. H0: μ ≥ 1056 Ha: μ < 1056 b. z= x − μ0 = 910 − 1056 1600 / 400 = −1.83 σ/ n Lower......

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...STAT 346/446 - A computer is needed on which the R software environment can be installed (recent Mac, Windows, or Linux computers are sufficient).We will use the R for illustrating concepts. And students will need to use R to complete some of their projects. It can be downloaded at http://cran.r-project.org. Please come and see me when questions arise. Attendance is mandatory. Topics covered in STAT 346/446, EPBI 482 Chapter 5 – Properties of a Random Sample Order Statistics Distributions of some sample statistics Definitions of chi-square, t and F distributions Large sample methods Convergence in probability Convergence in law Continuity Theorem for mgfs Major Theorems WLLN CLT Continuity Theorem Corollaries Delta Method Chapter 7 – Point Estimation Method of Moments Maximum Likelihood Estimation Transformation Property of MLE Comparing statistical procedures Risk function Inadmissibility and admissibility Mean squared error Properties of Estimators Unbiasedness Consistency Mean-squared error consistency Sufficiency (CH 6) Definition Factorization Theorem Minimal SS Finding a SS in exponential families Search for the MVUE Rao-Blackwell Theorem Completeness Lehmann-Scheffe Location and scale invariance Location and scale parameters Cramer-Rao lower bound Chapter 9 - Interval Estimation Pivotal Method for finding a confidence interval Method for finding the “best” confidence interval Large sample confidence......

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...proves true, then Whitners Autoplex has been charging far more less than surrounding, or even nationwide, auto dealers. Knowing the average cost of a vehicle is important to auto dealers because profit is what allows a business to prosper and grow. Problem Team D, believes the prices of vehicles has changes among the years. Team D, wants to gather information in order to find out why is it that the prices for a vehicle has varied among the years and among car dealers. Whitners Autoplex average price for a new vehicle is $22,000, while the national average for a vehicle in the United States is $30,748. As one can see, there is a great difference between the average at Whitners Autoplex and the national average. This research will helps Team D discover the variables involved in the difference between averages. Hypothesis When looking into the possible outcomes one can see that there are various. The hypothesis Team D chose is Whitners Autoplex prices differ from the national average. One outcome can be that Team D it is correct in the hypothesis established. Second outcome can be that it is inconclusive because of lack of reliable data. Third outcome is that the hypothesis it is not true and there is no conclusive reason the prices are different. Besides observing various possible outcomes, Team D also has to take a look at the variables involved. The variables involved in the data provided are age groups, amount of money spent, and domestic versus......

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