Element : Definition - Stat TrekDefinition of element , from the Stat Trek dictionary of statistical terms and
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on Stat ...

Survey Sampling Bias - Stat TrekDescribes two sources of bias in survey sampling: unrepresentative samples and
... The survey relied on a convenience sample, drawn from telephone ...

Random Number Generator | Random Number Table - Stat TrekThe numbers you generate appear in the Random Number Table . For help in
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Bayes ' Theorem - Stat TrekBayes ' theorem (also known as Bayes' rule) is a useful tool for calculating ... This
section presents an example that demonstrates how Bayes ' theorem can be ...

Chi - Square Test of Independence - Stat TrekThis lesson describes when and how to conduct a chi - square test of
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Regression Slope Test - Stat TrekTest method. Use a linear regression t-test (described in the next section) to
determine whether the slope of the regression line differs significantly from zero.

AP Statistics Practice Test - Stat TrekPractice test for multiple-choice section of the Advanced Placement (AP)
Statistics exam . Includes 40 questions , each with clear solutions.

Chi-Square Goodness of Fit Test - Stat TrekThis lesson explains how to conduct a chi-square goodness of fit test. The test is
applied when you have one categorical variable from a single population.

Poisson Distribution - Stat TrekA Poisson distribution is the probability distribution that results from a Poisson ...
The following notation is helpful, when we talk about the Poisson distribution .

Confidence Level : Definition - Stat TrekDefinition of confidence level , from the Stat Trek dictionary of statistical terms and
concepts. This statistics glossary includes definitions of all technical terms used ...

F Distribution Calculator - Stat Trek? A probability is a number expressing the chances that a specific event will
occur. This number can take on any value ...

Standard Error - Stat TrekThe standard error is an estimate of the standard deviation of a statistic. This
lesson shows how to compute the standard error , based on sample data.

Hypothesis Tests - Stat TrekThis assumption may or may not be true. Hypothesis testing refers to the formal
procedures used by statisticians to accept or reject statistical hypotheses.

Graphing Calculators - Stat TrekRecommended graphing calculators for AP statistics and calculus. ... (cable
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Margin of Error - Stat TrekIn a confidence interval, the range of values above and below the sample statistic
is called the margin of error . For example, suppose we wanted to know the ...

Random Number Generator - Stat TrekRandom Number Generator creates random number tables. Up to 1000 ... Each
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T distribution calculator finds cumulative probability and t scores. Fast, easy ...
text boxes. Click the Calculate button to compute a value for the blank text box. Which random variable should I ... - What are degrees of freedom?

Chi - Square Distribution - Stat TrekThe distribution of the chi-square statistic is called the chi - square distribution . In
this lesson, we learn to compute the chi-square statistic and find the probability ...

Measurement Scales - Stat TrekMeasurement scales are used to categorize and/or quantify variables. This
lesson describes the four scales of measurement that are commonly used in ...

Negative Binomial Distribution - Stat TrekIn this lesson, we cover the negative binomial distribution and the geometric
distribution. As we will see, the geometric distribution is a special case of the ...

Matrix Rank - Stat TrekThis lesson defines matrix rank and shows how to find the rank of a matrix .
Includes problems with solutions to illustrate key points.

Confidence Interval - Stat TrekThis lesson explains what a confidence interval is and explains how to construct
and interpret confidence intervals . Includes sample problem with solution.

one - sample t - test : Definition - Stat TrekDefinition of one - sample t - test , from the Stat Trek dictionary of statistical terms
and concepts. This statistics glossary includes definitions of all technical terms ...

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How to Test Hypotheses - Stat TrekHow to test hypotheses using four steps: state hypothesis, formulate analysis ...
This lesson describes a general procedure that can be used to test statistical ...

Sample Size Calculation: Simple Random Sample - Stat TrekThis approach works when the sample size is relatively large (greater than or
equal to 30). Use the first or third formulas when the population size is known.

Sample Size Calculation : Simple Random Sample - Stat TrekSample size calculation with simple random sampling. How to find smallest
sample size that provides desired precision. Sample problem illustrates key
points.

Margin of Error : Definition - Stat TrekDefinition of margin of error , from the Stat Trek dictionary of statistical terms and
concepts. This statistics glossary includes definitions of all technical terms used ...

Experimental Design - Stat TrekIntroduces experimental design – what it is and why it is useful in research.
Describes three common ... Experimental design in statistics : Video lesson. The
term ...

Experiment - Stat TrekIn an experiment , a researcher manipulates one or more variables, while holding
all other variables constant. By noting how the manipulated variables affect a ...

What is probability ? - Stat TrekWhat is probability ? Describes how to interpret probability . ... The probability of
an event refers to the likelihood that the event will occur. ... AP Statistics Tutorial.

Regression Slope : Confidence Interval - Stat TrekThis lesson describes how to construct a confidence interval around the slope of
a regression line. We focus on the equation for simple linear regression , which ...

Linear Regression - Stat TrekSimple linear regression . How to define least-squares regression line. How to
find coefficient of determination. Includes video lesson on regression analysis.

AP Statistics Formulas - Stat TrekHere are all of the formulas used on the Advanced Placement Statistics Exam.
Includes links to explanations that describe how to use each formula .

In a statistical experiment, the sum of probabilities for all possible outcomes is
equal to one. This means, for example, that if an experiment can have three ...

Binomial Calculator - Stat TrekUse the Binomial Calculator to compute individual and cumulative binomial
probabilities. For help in using the calculator , read the Frequently-Asked
Questions ... What is a binomial experiment? - What is a binomial distribution?

Statistics Notation - Stat TrekThis web page describes how symbols are used on the Stat Trek web site to
represent ... μ refers to a population mean; and x, to a sample mean . σ refers to
the ...

The Probability Calculator computes the probability of one event, based on
probabilities of other events. ... Click the Calculate button to create a summary
report.

Standard Deviation : Definition - Stat TrekDefinition of standard deviation , from the Stat Trek dictionary of statistical terms
and concepts. This statistics glossary includes definitions of all technical terms ...

Sample size calculation with simple random sampling. How to find smallest
sample size that provides desired precision. Sample problem illustrates key
points.

Stratified Sampling - Stat TrekDescribes stratified random sampling as sampling method. Covers proportionate
and disproportionate sampling. Lists pros and cons versus simple random ...

Hypothesis Test : Paired Means - Stat TrekHow to conduct a hypothesis test for the difference between paired means. The
test procedure, a matched-pairs t - test , is illustrated with a detailed example .

This lesson explains how to conduct a chi - square test for independence. The test
is applied when you have two categorical variables from a single population.

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Matrix Algebra Tutorial - Stat TrekDetermine matrix rank (i.e., distinguish singular from non-singular matrices). Find
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Chi Square Calculator - Stat TrekThe chi - square distribution calculator makes it easy to compute cumulative
probabilities, based on the chi - square statistic. For help, read the Frequently-
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This web site provides training and tools to help you solve statistics problems ...
trademarks of the College Board, which was not involved in the production of, ...

Simple Random Sampling - Stat TrekA sampling method is a procedure for selecting sample elements from a
population. A random number is a number determined totally by chance, with no
...

Simple Linear Regression Example - Stat TrekLinear regression example shows all computations step-by-step. How to find
regression equation , make predictions, and interpret results. Includes video
lesson.

Least squares linear regression - Stat TrekSimple linear regression. How to define least - squares regression line . How to
find coefficient of determination. Includes video lesson on regression analysis.

Normal Distribution - Stat TrekThe normal distribution refers to a family of continuous probability ... The normal
distribution is defined by the following equation: Normal .... Comparing data sets.

The Mean and Median: Measures of Central Tendency - Stat TrekThis lesson covers the mean and the median. Explains how to compute each
measure . Describes pros and cons. Includes sample problems and free video ...

Hypothesis Test for Mean - Stat TrekHow to conduct a hypothesis test for a mean value, using a one-sample t- test .
The test procedure is illustrated with examples for one- and two-tailed tests .

Combination and Permutation Calculator - Stat TrekCombination and permutation calculator. Finds the number of combinations and
permutations that result when you choose r elements from a set of n elements.

Influential Points in Regression - Stat TrekHow to identify influential points ( outliers ) that greatly affect slope of ... AP
Statistics Tutorial ... Statistics for People Who (Think They) Hate Statistics , 4th

Matrix Addition - Stat TrekMatrix addition and matrix subtraction. This lesson explains how to add matrices
and how to subtract matrices. Includes problems with solutions.

This web page describes how symbols are used on the Stat Trek web site to ... x
refers to a sample mean. s refers to the standard deviation of a sample. s2 refers
...

Discrete vs Continuous - Stat TrekDiscrete probability distributions vs continuous probability distributions. Discrete
random ... Some examples will clarify the difference between discrete and
continuous variables. Suppose the fire ... Counting data points. ▻ Probability
laws.

Independent Random Variables - Stat TrekWhen a study involves pairs of random variables , it is often useful to know
whether or not the random variables are independent . This lesson explains how
to ...

the most "typical" value in a set of values. Statisticians refer to the mean and
median as measures of central tendency . ... AP Statistics Tutorial. Exploring Data.

T distribution calculator finds cumulative probability and t scores. Fast ... Enter a
value for degrees of freedom. ... A t score is a statistic whose values are given by.

Boxplots - Stat TrekHow to interpret boxplots (aka, box and whisker plots ). How to to display
quantitative data with boxplots. Key points illustrated by examples. Plus free
video.

This lesson explains what a confidence interval is and explains how to construct
and interpret ... Often, the margin of error is not given; you must calculate it.

Suppose that a 90% confidence interval states that the population mean is
greater than 100 and ... Often, the margin of error is not given; you must calculate
it.

Simple linear regression. How to define least-squares regression line. How to
find coefficient of determination. Includes video lesson on regression analysis.

Variables in Statistics - Stat TrekCovers use of variables in statistics - categorical vs. quantitative, discrete vs.
continuous, univariate vs. bivariate data. Includes free video lesson.

two - sample t-test : Definition - Stat TrekDefinition of two - sample t-test , from the Stat Trek dictionary of statistical terms and
concepts. This statistics glossary includes definitions of all technical terms ...

Population : Definition - Stat TrekDefinition of population , from the Stat Trek dictionary of statistical terms and
concepts. This statistics glossary includes definitions of all technical terms used
on ...

This lesson explains what a confidence interval is and explains how to construct
and ... From the t Distribution Calculator , we find that the critical value is 1.96.

Proportion : Confidence Interval - Stat Trekwhere P is the population proportion , n is the sample size, and N is the .... From
the Normal Distribution Calculator , we find that the critical value is 2.58. Compute
...

Free tutorials cover statistics , probability, and matrix algebra. ... This web site
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