Stats Notes Week Two Describing Data Mean-average (takes every value into account- Sum of all Values/total number of values=mean Median-what data is in the middle (exact middle value)? Mode-what value occurs most frequently in the data? Interval and Ratio Data Nominal Ordinal Interval-best data Ratio-best data Measures of Variation Outlier-high-end/low-end Interpret the measures of central tendency-mean‚ median‚ mode Measures of variability-range‚ standard deviation (SD) =square root
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HCS/438 DQ’s Week 1: DQ1: What are the differences between descriptive and inferential statistics? According to Bennett (2009)‚ the biggest difference between descriptive and inferential statistics is that descriptive statistics "deals with describing raw data in the form of graphics and sample of statistics" and inferential statistics "deals with estimating population parameters from sample data." This means that inferential statistics would be an estimate because the data would be estimated
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University of Phoenix HCS/438 (Statistical Applications ) Quiz#2 - 2-25-2012 - Esmaail Nikjeh Name: ________________________ True or False Questions; Please select the correct answer. (1 points each) T F 1. The probability that X takes on a value that is between 3 and inclusive of 4 can be written as P(3 < X ( 4). T F 2. P(X > x ) + P(X < x) + P(X = x) = 1. T F 3. If P(X > x) = 0.34 and P(X = x) = 0.10‚ then P(X ( x) = 0.56. T F 4- Using the classical viewpoint‚ the probability
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understanding of hypothesis testing. The textbook explained the aspects and steps of hypothesis testing in a legible fashion‚ while the video helped demonstrate a real-life application. I learned from the text that hypothesis testing is a “Procedure for deciding whether the outcome of a study (results from a sample) supports a particular theory or practical innovation (which is thought to apply to a population)” (Aron A.‚ Aron‚ E.‚ and Coups‚ 2011‚ p. 145). I also learned that hypothesis testing
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Release date: 27 April 2014 Submission date: 9 May 2014 TUTORIAL ON HYPOTHESIS TESTING (1) Basic Concept 1. State the null and alternative hypothesis for each conjecture : a. A researcher thinks that if expectant mothers use vitamin pills‚ the birth weight of the babies will increase. The average birth weight of the population is 3.0kg. b. An engineer hypothesizes that the mean number of defects can be decreased in a manufacturing process of compact disks by using robots instead of humans
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Hypothesis Testing I Pat Obi What is a “Hypothesis?” A statement or claim about the value of a population parameter: μ‚ σ2‚ p Pat Obi‚ Purdue University Calumet 2 Decision Rule 1. x 0 Z s n Compare calculated Z value to Z value from Table (critical Z value) Reject H0 if calculated Z value lies in the rejection/significance region (i.e. region) ALTERNATIVELY: 2. Compare p-value to Reject H0 if p-value < Pat Obi‚ Purdue University Calumet 3 Two-Tail Test Ex: H0: 0
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HYPOTHESIS TESTING WHAT IS THIS HYPOTHESIS???? • In simple words it means a mere assumption or supposition to be proved of disproved. • But‚ for a researcher it is a formal question that he intends to resolve. • Example: I assume that 1) under stress and anxiety a person goes into depression. 2) It leads to aggressive behaviour. Eg. : Students who get better counselling in a university will show a greater increase in creativity than students who were not counselled. • So‚ the hypothesis
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CHAPTER 8 Introduction to Hypothesis Testing 8.1 Inferential Statistics and Hypothesis Testing LEARNING OBJECTIVES 8.2 Four Steps to Hypothesis Testing After reading this chapter‚ you should be able to: 8.3 Hypothesis Testing and Sampling Distributions 8.4 Making a Decision: Types of Error 8.5 Testing a Research Hypothesis: Examples Using the z Test 8.6 Research in Focus: Directional Versus Nondirectional Tests 8.7 Measuring the Size
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Hypothesis testing I Kevin Soo Outline • • • • Theory and the research process What is a hypothesis? Hypothesis testing Statistical models Theory and the research process Theory • A belief – Can be true or false – P (belief) • A proposed/possible explanation for something – ‘Some students do poorly at statistics because they have less exposure to mathematics’ – ‘Women don’t date me because I’m ugly’ – ‘Manchester United lost the Premier League because they struggled with injury
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Hypothesis Testing The sole purpose of hypothesis testing is to determine whether or not research that has been collected is proved or disproved; usually allowing up to a 5% error factor. By using this 5% margin of error a researcher can consider the question of research being conducted is proven. There are five steps to be followed in doing hypotheses testing. The steps are: developing the research question‚ specifying between null and alternative hypotheses‚ calculating the statistic‚ computing
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