AQA GCSE Statistics key terms

A responsibility to respect participants’ rights, dignity and well-being when conducting an investigation.

A critical assessment of a statistical investigation that identifies weaknesses, considers their effects and suggests improvements.

A probability of $\frac{1}{2}$, $0.5$ or $50\%$: an event is equally likely to happen as not to happen.

A specified outcome or collection of outcomes of a probability experiment.

The predicted number of times an event will occur, calculated as the number of trials multiplied by its theoretical probability.

An investigation of how changes in an explanatory variable affect a response variable.

An estimate of probability calculated by dividing the number of times an event occurs by the total number of trials. It is also called relative frequency.

The variable whose values or categories are used to explain or predict differences in a response variable. It may be deliberately changed or simply observed. Also called the independent variable.

Notation that is unnecessary within data entries used for processing, such as repeated unit labels when the unit is already stated in the column heading.

A factor other than the one being investigated that could affect the outcome of an experiment.

Estimating an unknown value outside the range of the observed data.

A data value that is unusually large or small compared with the other values in a dataset.

An experiment conducted in an everyday setting where the researcher deliberately changes a variable.

A spreadsheet operation that displays only records meeting chosen conditions, while hiding rather than deleting the other records.

The mean of four consecutive observations in a time series.

The number of times a value or category occurs in a dataset.

The frequency per unit of class width, calculated using $\text{frequency density}=\frac{\text{frequency}}{\text{class width}}$.

A graph formed by plotting each class frequency against its class midpoint and joining consecutive points with straight lines.

A predefined spreadsheet formula that performs a calculation, such as SUM or AVERAGE.

The overall direction of change in data over time, which may be rising, falling or level.

For $n$ positive values, the $n$th root of their product. It is useful for averaging factors that multiply together.

The change in y for each increase of one unit in x; the coefficient $b$ in $y=a+bx$.

A misleading or incorrect impression of data caused by the way it is displayed.

The total value of goods and services produced within a country during a specified period.

Data summarised in class intervals rather than as individual values.

A table recording how many observations fall within each class interval, rather than recording every individual value.

A diagram for grouped continuous data in which bar areas, rather than heights alone, represent frequencies.

A statement that can be investigated using statistical data.