Ex a sample of 765 voters exit polled on election day

ex. a sample of 765 voters exit polled on election day.
Parameter: A descriptive measure of a population. Populations have parameters, samples have
statistics
Statistic: A descriptive measure of a sample
Confidence level: The proportion of times that an estimating procedure will be correct.
ex. a confidence level of 95% means that, estimates based on this form of statistical inference
will be correct 95% of the time.
Significance level: WHen the purpose of the statistical inference is to draw a conclusion about a
population. Measures how frequently the conclusion will be wrong in the long run.
ex. a 5% significance level means that, in the long run, this type of conclusion will be wrong 5%
of the time.
Chapter two
Variable: Some characteristic of a population or sample
ex. student grades represented by a capital letter

Values: Range of possible values of the variable
ex. student marks (0...100)
Data: The observed values of a variable
ex. student marks { 67, 74, 71, 83, 93, 55, 48}
Types of Data and Information
● Interval Data
○ Real numbers
○ Also referred to as quantitative or numerical
● Nominal Data
○ The values of nominal data are categories
○ categorical
○ Qualitative or caterorical
○ ex. responses to questions about marital status, codes as: Single = 1, Married =