7th Grade Statistics and Probability

Population

Number of items from which data might be collected

Sample

One or more observations about the population

Unbiased

Random

P(event)=

# of wanted outcomes over # of total outcomes

Impossible

0%

Unlikely

25%

As likely as not

50%

Likely

75%

Certain

100%

Outcome

A possible result of a probability experiment

Probability

likelihood that a particular event will occur

Theoretical Probability

What should occur or what we expect to happen in an experiment

Experimental probability

Probability-based on data from repeating an event (doing an experiment)

Complement

something that completes or makes up a whole

Random sample

a sample that fairly represents a population because each member has an equal chance of inclusion.

Bias

prejudice in favor of or against one thing, person, or group compared with another, usually in a way considered to be unfair.

Tree diagram

A diagram used to show the total number of possible outcomes

Equally likely

Outcomes that have the same probability

Representative

this kind of sample accurately reproduces the characteristics of the population a researcher is studying.