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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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 for certain tasks. The
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Hypothesis Testing: Alzheimer ’s Disease Natalie Sullivan PSY/315 August 8‚ 2011 Deborah Suzzane Ph.D. Hypothesis Testing: Alzheimer ’s Disease One in eight American’s over age 65 are diagnosed with Alzheimer’s disease. This number continues to grow as the population increases. The number of people affected by Alzheimer’s is alarming. The Alzheimer’s Association (2011) estimates that 5.4 million Americans of all ages suffer from this disease. Team A will attempt to form a hypothesis stating
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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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Table of Contents Frequencies: Statistics RESPONDED GENDER HSC GPA STUDY HOUR N Valid 75 75 75 Missing 0 0 0 Mean 1.51 4.8520 4.5600 Median 1.51a 4.9442a 4.5094a Mode 2 5.00 4.00 Std. Deviation .503 .23673 1.00324 Variance .253 .056 1.006 Skewness -.027 -1.608 .408 Std. Error of Skewness .277 .277 .277 Kurtosis -2.055 1.864 -.117 Std. Error of Kurtosis .548 .548 .548 Range 1 1.00 4.00 Sum 113 363.90 342.00 Percentiles
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Inferential Statistics Article Critique Dawn Rivenburg PSY 325 Statistics for the Behavioral & Social Sciences Instructor: Jeral Kirwan January 16‚ 2017 In the article‚ Differential Effects of a Body Image Exposure Session on Smoking Urge Between Physically Active and Sedentary Female Smokers‚ the goal of the researchers was to assess the correlation of physical activity and smoking urges of women ages 18-24 years old. The researchers were also concerned with the effect of negative body
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KEYWORDS: t test for mean difference‚ assumption 3. If we are testing for the difference between the means of 2 related populations with samples of n1 = 20 and n2 = 20‚ the number of degrees of freedom is equal to a) 39. b) 38. c) 19. d) 18. ANSWER: c TYPE: MC DIFFICULTY: Easy KEYWORDS: t test for mean difference‚ degrees of freedom 4. If we are testing for the difference between the means of 2 independent populations with samples
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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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062896401 Home Size 31.69164882 24.44661008 1.296361692 0.223968044 The formula for the coefficient of correlation‚ . = 0.076. a. Compute the coefficient of correlation is .308 b. Determine the coefficient of determination. Regression Statistics Multiple R 0.37931016 R Square 0.143876197 Adjusted R Square 0.058263817 Standard Error 15.25058359 Observations 12 The coefficient of determination is 14%. b. Determine the coefficient of determination is .095 c. Can we conclude that
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