Last name: First name: Student #: STA 304H1 F/1003H F SUMMER 2009‚ First Test‚ May 28 (20%) Duration: 50min. Allowed: hand-calculator‚ aid-sheet‚ one side‚ with theoretical formulas and definitions only. [25] 1) A marketing analyst is asked to study the buying habits of shoppers at a national chain store (e.g. Sears). Suppose there are 150 stores around the country. (a) Describe the population of interest. (b) Describe in short a realistic sampling procedure for obtaining a representative
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5.23 Let x be a normally distributed random variable having mean = 30 and standard deviation . Find the z value for each of the following observed values of x: In each case‚ explain what the s value tells us about how the observed value of x compares to the mean 5.29 Weekly demand at a grocery store for a brand of breakfast cereal is normally distributed with a mean of 800 boxes and a standard deviation of 75 boxes‚ a. What is the .probability that weekly demand is (1) 959 boxes or less? (2) More
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1. A recent issue of Fortune Magazine reported that the following companies had the lowest sales per employee among the Fortune 500 companies. [20 Marks] | |Company |Sales per Employee ($1000s) |Sales Rank | | |Seagate Technology |$42.20 |285 | | |SSMC | 42.19
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G036 * Yes because the p-value is less than 0.05 or No‚ because the p-value is greater than 0.05 * The coefficient of variation is the standard deviation of a data set‚ divided by the mean of the same data set. * Z score = x -ms * The Independent part is what you‚ the experimenter‚ changes or enacts in order to do your experiment. The dependent variable is what changes when the independent variable changes - the dependent variable depends on the outcome of the independent variable
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Random Sample: each member of the population has the same chance of being selected Representative Sample: characteristics should represent those of the target population without bias Observational Study: no intervention by the investigator‚ no treatment imposed Experimental Study: investigator has some control over the determinant Variables: Categorical – each observation falls into a finite number of groups Nominal: named variables with no implied order e.g. personality type Ordinal:
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Harrisburg High school was bully central. 75% of all students were either being bullied or doing the bullying‚ unaware of the damage being done. Students who bully are some of the leading causes of death due to suicide by those bullied. The effects on teenagers are possible suicide and low self-esteem‚ one possible solution would be counseling for those who bully. To begin‚ an effect of bullying on teenagers is possible suicide. Kayla Marcella would be 19 years old this year .Marcella committed
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Term Random Variable Definition A variable that takes on different numerical values based on chance Term Discrete Random Variable Definition A random variable that can only assume a finite number of values or an infinite sequence of values such as 0‚1‚2‚3.... Term Continuous Random Variables Definition Random variables that can assume any vallue in an interval. Term Expected Value Definition The mean of a probability distribution. the average value when the experiment
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GMB 713 PROBLEM SET NO. 2 PROBLEM SOLVING: Solve the following problems. Show all pertinent solutions. 1. A car battery dealer is trying to determine which of the brands of car battery he is selling has a longer life span. He conducted an investigation by interview his customers and was able to get the following results: Brand X Brand Y Mean life span 4.5 years 4.9 years Standard deviation
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Math 221 Quiz Review for Weeks 3 and 4 1. State whether the variable is discrete or continuous. The # of keys on each student’s key chain. 2. Decide whether the experiment is a binomial experiment. Explain why by citing the properties of binomial experiments. Testing a pain reliever using 20 people to determine if it is effective. The random variable represents the number of people who find the pain reliever to be effective. 3. Use the binomial probability distribution to answer the following
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Prepare a managerial report for the dean of the college that summarizes your assessment of the nature of cheating by business students at Bayview University. Be sure to include the following questions. 1. Develop 95% confidence intervals for the proportion of all students‚ the proportion of male students‚ and the proportion of female students who were involved in some type of cheating. 2. Conduct a hypothesis test to determine if the proportion of business students at Bayview University who were
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