Chapter 18 : Inferential Statistics
BASICS
SAMPLING DISTRIBUTIONS
ESTIMATION
HYPOTHESIS TESTING
SIGNIFICANCE TESTS
Inferential Statistics
Sample Vs Population
Statistics Vs Parameter
Study samples not populations
Symbols
definition
repeated sampling
sampling error
standard error
sampling distribution of mean **
Point Estimation
single value
sampling error
Interval Estimation
range of numbers
confidence interval
probability
including the population parameter
Null Hypothesis
Alternative Hypothesis
sample data reject or support null hypothesis
Directional alt. hypothesis**
P-value / alpha
significant level
Decision
statistically significant?
Decision Matrix
Type 1 & type 2 error
Steps in hypothesis testing
Controlling the risk
large sample size
power
practical significance
effect size
t-test for independent samples
t values
large = either end of tail
one way ANOVA
2 / more group means
F value
no r/s F = 1.0
Post Hoc Test
which one?
p value, sig. level
p values, sig. level
p value, sig. level
t-test // correlations coefficients
p. value, sig. level
variance
square the correlation coefficients and turn it into %
t-test // regression coefficients
chi-square test // contingency tables
p. value, sig. level
semi partial correlation squared
p. value, sig. level
effect size indicator