people with cholesterol levels over 200. In order to determine if this is a valid claim‚ they hire an independent testing agency‚ which then selects 25 people with a cholesterol level over 200 to eat their cereal for breakfast daily for a month. The agency should be testing the null hypothesis H0: μ = 10 and the alternative hypothesis B 6. Ha: μ >10. Suppose we are testing the null hypothesis H0: μ = 20 and the alternative Ha: μ 20‚ for a normal population with σ = 5. A random sample of 25 observations
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Examples When examining the effect of a factor‚ it is often helpful to remove the effect of excess variation through the use of blocking. A blocking variable is one that may affect the variation of the response‚ but is unrelated to the primary hypothesis of interest. The desired result is to have homogeneous experimental units within each block so that when the blocking effect is removed (through modeling)‚ all individuals can be considered homogeneous before receiving the treatments. The term randomized
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Designed to study “laws” of behavior; Historically significant 4) between subjects: diff groups assigned to diff levels (control) 5) order effects: (testing effects): problem in within subject design; occur when participants are tested more than once in a study with early testing affecting later testing. 6) counterbalancing (combats testing effects): change the order; controlling for the effects of an extraneous variable by ensuring that its effects are equal in all treatment conditions. For
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I. Probability Theory * A branch of mathematics concerned with the analysis of random phenomena. The outcome of a random event cannot be determined before it occurs‚ but it may be any one of several possible outcomes. The actual outcome is considered to be determined by chance. * The word probability has several meanings in ordinary conversation. Two of these are particularly important for the development and applications of the mathematical theory of probability. One is the interpretation
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EG381: Module 4 Hypothesis Testing Exercise 4.1 Task 1: Solve the following problems: A student of the author surveyed her friends and found that among 20 males‚ 4 smoke and among 30 female friends‚ 6 smoke. Give two reasons why these results should not be used for a hypothesis test of the claim that the proportions of male smokers and female smokers are equal. First‚ the sample is not random‚ it is a convenience sample and therefore cannot be trusted. Second‚ np҄ = x = 4 < 5‚ therefore
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World Journal of Agricultural Sciences 8 (6): 568-584‚ 2012 ISSN 1817-3047 © IDOSI Publications‚ 2012 DOI: 10.5829/idosi.wjas.2012.8.6.1688 An Insight in Statistical Techniques and Design in Agricultural and Applied Research Ajay S. Singh and Micah B. Masuku Department of Agricultural Economics and Management‚ Faculty of Agriculture‚ University of Swaziland‚ Swaziland Abstract: Advance applied science researches have experienced a dramatic change in knowledge and an exponential increase
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1 Objectives of the Course • • • • To provide a formal quantitative approach to problem solving To give an intuition for managerial situations where a quantitative approach is appropriate To introduce some widely used quantitative models To introduce software for solving such models. 2 Must-Read Article Inventory • • • • “Decision trees”‚ Robin Greenwood (HBR‚ March 2006) “Note on Linear Programming”‚ Jonathan Eckstein (HBR‚ November 1992) “Sampling and Statistical Inference”‚ Arthur
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a set of t-tests to compare mean seasonal rainfalls 1.2.1. Frame Hypotheses for a set of t-test to compare mean seasonal rainfalls of Winter Rain and pre Monsoon Rain State the Null Hypothesis: The mean seasonal amount of rainfalls of Winter Rain is equal to the pre Monsoon Rain. State the Alternative Hypothesis: The mean seasonal amount of rainfalls of Winter Rain is not equal to the pre Monsoon Rain. State the Level of significance: State the Test Statistic: We use t- test as a test statistic
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also stated the two hypotheses to be tested: the null hypothesis that the population is equal to 12 and the alternative hypothesis that the mean is not equal to 12. This indicates a two tailed tests to determine whether or not to reject the null hypothesis. The 4 provided sample sizes each contained 30 observations‚ indicating a normal distribution and z test statistics. Methodology The first question required conducting a hypothesis test for each sample at the .01 level of significance.
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MBA SEMESTER 1 MB0040 – STATISTICS FOR MANAGEMENT Assignment Roll No. 1- Statistical survey is a scientific process of collection and analysis of numerical data used to collect information about units. Questionnair and schedule are both methods of collecting data in statistical survey. At questionnair the questions is sent by mail to respondents to fill it and send it back. At schedule the questions is filled by the enumerator. Questionnair is a cheaper process than schedule when it was
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