Chapter-7hypothesiststing for quantitative variable 2021/1/29 1
2021/1/29 1
●●● ●●●● ●●●●● contents ●●●● ●●0●● ●●●● ●●●● 1 introduction 2. Hypothesis testing 2. 1 One sample t test 2.2 two independent-samples t test 2.3 Paired-samples t test 21/1/29
2021/1/29 2 contents 1. introduction 2. Hypothesis testing 2.1 One sample t test 2.2 two independent-samples t test 2.3 Paired-samples t test
●●● ●●●● Hypothesis testing ●●●●● ●●●● Aim: Is the average English score of students from 2 0000 ●●●● schools different or same? Methods 1. Compute and compare two population mean directly ≠ XINI 21/1/29
2021/1/29 3 Hypothesis testing Aim: Is the average English score of students from 2 schools different or same? Methods1. Compute and compare two population mean directly 1 2 1 2 =
●●● ●●●● Hypothesis testing ●●●●● ●●●● Aim: Is the average English score of students from 2 0000 ●●●● schools different or same? Methods 2 Do a sampling study and then do hypothesis testing =100 X1=82,S1=9.5 =150 X2=81 8.3 XINI 2021/1/29
2021/1/29 4 Hypothesis testing Aim: Is the average English score of students from 2 schools different or same? Methods 2 Do a sampling study and then do hypothesis testing 82, 9.5 100, 1 1 1 = = = X S n 81, 8.3 150, 2 2 2 = = = X S n 1 2 =
●●● ●●●● ●●●●● ●●●● The reason that81≠82 ●●0●● ●●●● ●●●● y True difference between two population means √ Chance( sampling error So the hypothesis task is to differentiate that the difference between two samples is from the true difference between two population means or from chance 21/1/29
2021/1/29 5 The reason that ✓ True difference between two population means. ✓ Chance (sampling error) So the hypothesis task is to differentiate that the difference between two samples is from the true difference between two population means or from chance. 81 82