AP Statistics The Role of Statistics Terms
Histogram
A graph of vertical bars in intervals representing the frequency distribution of a set of data.
Statistics
The scientific discipline that provides methods to help us make sense of data.
Variability
In a
Quantitative
A variable whose values are counts or measurements.
Random Digit Table
A chance device that is used to select experimental units or conduct simulations.
Random Phenomena
Those outcomes that are unpredictable in the short term, but nevertheles
Geometric Distribution
The probability distribution of a geometric random variable X. All possible outcomes of X
before the first success is seen and their associated probabilities.
Geometric Random Variable
A random variable X (a) that has two possible o
Addition Rule
P(A B) = P(A) + P(A) - P(A B) aids in computing the chances of one of several events
occurring at a given time.
Alpha ()
The probability of a Type I error. See significance level.
Alternative Hypothesis
The hypothesis stating what the resear
roundoff error
the error that occurs when the percents don't add up to 100%
pie chart
This must include all the categories that make up a whole. Use this only when you want to
emphasize each category's relation to the whole. It is awkward to make by hand,
Observational Study
the measurement of data from individuals without trying to influence the responses
Experiment
imposes a treatment on the individuals and observes the responses
Population
the group that makes up all the individuals of interest
Sample
t
anecdotal data
Data collected from haphazardly selected individual cases, which often come to attention
because they're striking in some way.
available data
Data that has been collected in the past, probably by someone else, and are available for your
use
Addition Rule
P(A B) = P(A) + P(A) - P(A B) aids in computing the chances of one of several events
occurring at a given time.
Alpha ()
The probability of a Type I error. See significance level.
Alternative Hypothesis
The hypothesis stating what the resear
statistics
the science (and art) of learning from data
data
numbers with a context
probability
the study of chance behavior
population
large group
sample
smaller group
available data
data that were produced in the past for some other purpose but that may
1 Proportion Z Test Checks
1. Individuals are independent. 2. 10% Condition (less than 10% all population) 3. nphat/nqhat >
10 4. Random
1 Proportion Z Interval Margin of Error
ME=Z* (p q )/n)
1 Prop Z Interval Equation
phatME
Z Interval: SE or SD?
SE (ph
Random
An outcome is _ if we know the possible values it can have, but not which particular value
it takes.
Simulation
A _ models a real-world situation by using random-digit outcomes to mimic the
uncertainty of a response variable of interest.
Simulation
Nonresponse Bias
The situation where an individual selected to be in the sample is unwilling, or unable, to provide
data.
Normal Distribution
A continuous probability distribution that appears in many situations, both natural and manmade. It has a bell-sh
Matched Pairs
a technique whereby each participant is identical to one other participant in terms of a third
variable
Conditional Probability
the probability that an event will occur given that one or more other events have occurred
Mode
the most frequent