Stats CP1 Vocab Review

In a statistical study, the entire group of individuals about which we want information. 

Has mean 0 and standard deviation 1.

An important class of density curves that are symmetric, single-peaked, and bell-shaped.

The difference between an observed value and the value predicted by the regression line.  

Occurs when a selected individual cannot be contacted or refuses to cooperate.

Maximum value minus the minimum value. 

The arithmetic average.

Displays the distribution of a quantitative variable. 

A graph of the five-number summary. 

A variable that measures an outcome of a study. 

A number that describes some characteristic of the population.

Describes a graph of quantitative data with two clear peaks. 

The number such that half the observations are smaller and the other half are larger. 

Individuals to which treatments are applied.

Study designs that involve making two observations on the same or two similar individuals.

Occurs when some members of the population are left out of the sampling frame.

The average squared distance of the observations in a data set from their mean. 

Measures the direction and strength of the linear relationship between two variables.

Is completely specified by two numbers, mean μ and standard deviation σ. 

A sample selected by taking the members of the population that are easiest to reach. 

Difference of third and first quartiles.

Groups of individuals that are similar in some way that might affect their responses. 

The design of a statistical study systematically favors certain outcomes. 

A simple graph that shows each data value as a dot above its location on a number line. 

Minimum Q1 M Q3 Maximum 

Experimental units that are human beings. 

Measures the average distance of the observations from their mean. 

An observation that if removed it would markedly change the result of the calculation.

A variable that helps explain or influences changes in the other variable. 

Used to compare the distribution of a quantitative variable for two groups. 

Has the general form: estimate ± margin of error.

Deliberately imposes some treatment on individuals to measure their responses. 

An individual value that falls outside the overall pattern of a distribution. 

A number that describes some characteristic of a sample.

Describes the spread.

An inactive (fake) treatment. 

Tells how many standard deviations a data point is from mean.

A specific value of an explanatory variable (factor) in an experiment.

The most important influence on the answers given to a survey. 

Gives every possible sample of a given size the same chance to be chosen. 

A study that attempts to collect data from every individual in the population. 

Also known as the "empirical rule." 

The amount by which y is predicted to change when x increases by one unit. 

All individuals in the chosen group are included in the sample. 

Can be described by the direction, form, and strength of the relationship.