Statistics and probability (IB)

Population

Every single person or thing we're interested in studying.

Sample

A smaller group taken from the population to represent the whole.

Random Sample

A sample where everyone has the same chance of being chosen, similar to picking names out of a hat.

Discrete Data

Data that can only take certain separate values, usually whole numbers.

Continuous Data

Data that can take any value within a range, often involving measurements.

Reliability

The trustworthiness of information in statistics.

Bias

When a sample does not fairly represent the whole group being studied.

Outliers

Observations that deviate markedly from the predominant pattern of a dataset.

Frequency Distribution

A tabulation or graphical representation that organizes observed data.

Histogram

A bar graph used to depict the frequency distribution of continuous data.

Cumulative Frequency Graphs

Graphs that illustrate the accumulated frequency of data values up to and including each interval.

Box and Whisker Diagrams

Graphs that visually summarize a dataset's distribution, showing median, quartiles, and outliers.

Mean

The arithmetic average of a dataset.

Median

The central value that divides a dataset into two equal halves.

Mode

The most frequent value in a dataset.

Range

The difference between the maximum and minimum values in a dataset.

Variance

A measure of the average squared differences from the mean.

Standard Deviation

The square root of the variance, indicating the degree of data spread.

Correlation

A measure quantifying the intensity and direction of the linear association between two variables.

Regression

A statistical method used to model the linear relationship between two variables.

Probability

A numerical quantification of the likelihood of a particular event's occurrence.

Trial

A singular performance or instance of an experiment.

Outcome

A specific observable result from a trial.

Expected Value

The theoretical average value of a discrete random variable over many trials.

Binomial Distribution

A discrete probability distribution representing the number of successful outcomes in a set of independent Bernoulli trials.

Normal Distribution

A continuous probability distribution that is symmetric and bell-shaped.

Standard Normal Distribution

A normal distribution with a mean of zero and a standard deviation of one.