Confidence interval
Confidence interval premise: data must be normally distributed
Confidence interval: Analysis - Descriptive statistics - Exploration - Statistics - Descriptive - set confidence interval confidence - continue - Select the variable - OK
Meaning 95% confidence interval of the mean: If we repeat the whole extracted from a sample capacity of 100 n, then the samples from the mean confidence interval 100, at least 95 contain the Mean
Ideological assumptions
Hypothesis testing ideas: reductio ad absurdum and small probability principle
Hypothesis testing is possible to make two types of errors:
Type I error: null hypothesis is correct, but wrong to refuse him and refused to really wrong
Type II error: null hypothesis is not correct, but the error did not refuse him, and by false alarms