Introduction to Statistics

numerical characteristic

Statistic- ________ of a sample, a variable quantity (changes from sample to sample)

Population

________- the total set of all "individuals "of interest.

Inferential statistics

________- methods for drawing conclusions about a population.

Descriptive statistics

________- methods for organizing and summarizing information.

presence of variability

Statistics- the science of learning from data in the ________.

Statistics

the science of learning from data in the presence of variability

Three main reasons for studying statistics:

Being informed

Making good decisions

Evaluating decisions that affect you

How does statistics vary from mathematics:

Role of context
Logic of statistical inference

Population

the total set of all “individuals” of interest

Sample

a subset of “individuals” selected from the population

Parameter

numerical characteristic of a population, a fixed quantity

Statistic

numerical characteristic of a sample, a variable quantity (changes from sample to sample)

Statistical questions

A question that can be answered by collecting data that varies

many possible vantage points; no single answer

What do you need to identify in a statistical question?

the population

the variable

the variation

Statistical problem solving process

Formulate a statistical research question

Collect data

Analyze data

Interpret results

Three main components of statistics

Describing data
producing data
Drawing conclusions from data

Descriptive statistics

methods for organizing and summarizing information

Inferential statistics

methods for drawing conclusions about a population

Categorical variable

non-numerical variable with different categories

Quantitative variable

numerical variable

Discrete variable

its possible values form a set of separate numbers (something that can be counted)

Continuous variable

its possible values form a continuum of values over the real number line (something that can be measured)