What is a Hypothesis? 关于总体参数的假设 A hypothesis is an I assume the mean gpa assumption about the of this class is 3.5! population parameter. 口 A parameter is a Population mean or proportion 口 The parameter must be identified before analysis ?1984-1994 TMaker Co
A hypothesis is an assumption about the population parameter. A parameter is a Population mean or proportion The parameter must be identified before analysis. I assume the mean GPA of this class is 3.5! ?1984-1994 T/Maker Co. What is a Hypothesis? 关于总体参数的假设
The Null Hypothesis, Ho 无效假设 States the Assumption (numerical) to be tested e.g. The average TV sets in US homes is at least 3(H0:u>3) Begin with the assumption that the null hypothesis iS TRUE. (Similar to the notion of innocent until proven guilty o Refers to the Status Quo .Always contains the ?=?sign The Null Hypothesis may or may not be rejected
• States the Assumption (numerical) to be tested e.g. The average # TV sets in US homes is at least 3 (H0 : m >3) • Begin with the assumption that the null hypothesis is TRUE. (Similar to the notion of innocent until proven guilty) The Null Hypothesis, H0 无效假设 •Refers to the Status Quo •Always contains the ?= ?sign •The Null Hypothesis may or may not be rejected
The Alternative Hypothesis, HI 被择假设 Is the opposite of the null hypothesis e.g. The average TV sets in US homes is less than3(H1:μ<3) Challenges the status Quo Never contains the ??sign The Alternative Hypothesis may or may not be accepted
• Is the opposite of the null hypothesis e.g. The average # TV sets in US homes is less than 3 (H1 : m < 3) • Challenges the Status Quo • Never contains the ??sign • The Alternative Hypothesis may or may not be accepted The Alternative Hypothesis, H1 被择假设
Identify the problem 解决问题的步骤 Steps: a State the Null Hypothesis (Ho: u=3) a State its opposite, the Alternative Hypothesis(H1:μ<3) o Hypotheses are mutually exclusive exhaustive e Sometimes it is easier to form the alternative hypothesis first
Steps: State the Null Hypothesis (H0 : m = 3) State its opposite, the Alternative Hypothesis (H1 : m < 3) ⚫ Hypotheses are mutually exclusive & exhaustive ⚫ Sometimes it is easier to form the alternative hypothesis first. Identify the Problem 解决问题的步骤
Hypothesis Testing process 假设检验过程 Assume the population mean age is 50 (Null Hypothesis) Population lsX=20=50? The Sample Mean Is 20 No, not likely ■■■■I ■■■ Null Hypothesis 回■ Sample
Population Assume the population mean age is 50. (Null Hypothesis) REJECT The Sample Mean Is 20 Null Hypothesis Sample Is X = 20 m = 50? Hypothesis Testing Process 假设检验过程 No, not likely!