Applet
Sites
Descriptive
Statistics
- Mean
and Median. A
comparison between the mean and median is shown as you paint a
histogram.
Normal
Distributions
- Normal
Probability Calculator. Probabilities
are
calculated and drawn from a standard normal distribution between two
given
z-scores.
- Normal
Approximation to the Binomial. For certain values from a
given
binomial distribution, the binomial probability is compared to its
normal
approximation.
- Quincunx.
As balls fall through a field of pins they are
collected
at the bottom and form an approximate normal (or binomial where p =
0.5)
distribution.
Other
Distributions
Sampling
Distributions and the Central Limit Theorem
- Sampling
Distribution. This is a very nice
applet.
You are allowed to choose a parent population (normal, uniform, skewed
or custom) from which to draw. Different different types of
sampling
distribution can then be formed.
- Rolling
Dice. You control the number of dice and how many times they
are rolled. A relative frequency histogram of the results is
shown.
- More
Rolling Dice. Similar to the previous dice applet except the
vertical axis on the frequency histogram remains at a constant scale.
Regression
and Correlation
- Influential
Points. A scatterplot with a regression
line are given and you are allowed to add an additional point to see
the
affect it has on the regression line and the correlation.
- Errors
and Residuals. You plot your own points with the mouse and a
regression line with vertical error lines is made. A residual
plot
is also constructed.
- Estimating
Regression and Correlation. A scatterplot is given and 5
different
correlation values are shown. You are to estimate which
correlation
is correct and draw in the regression line. The correct answers
are
then given.
- Guessing
correlations. Four scatterplots and four correlations are
given.
You have to match them up. You can repeat this process to see
what
percent you can get correct.
- Putting
Points. You are allowed to plot your own points and the
regression
equation and correlation are calculated throughout the process.
Confidence
Intervals
- Confidence
Intervals for a Population Mean.
Sampling
is done from a population with a mean of 50 and a population of
10.
You can adjust the sample size and then 100 samples are then
taken.
For each of these samples, 95% and 99% confidence intervals are
computed
and shown graphically.
- Confidence
Interval for a Population Proportion.
For
a specified sample size and population proportion, a large number of
samples
are taken and 95% confidence intervals are calculated. The number
of intervals that contain the population proportion is then
reported.
You see how both the sample size and the population proportion affect
this
percentage.
Tests
of Significance
Tests
of Proportions. You can adjust the alpha level, the form of
the
hypotheses, or make p different from p_{0}.
Sixty samples of size 30 are then drawn. The applet graphically
shows
the samples where the null is rejected as well as those where the null
is not rejected.
Random
Marble Grabber. You can draw marbles out of a bag and a
chi-square
test statistic is calculated on the premise that the colors are evenly
distributed.
Probability
- Venn
Diagram Applet. A Venn diagram for two non-disjoint
sets are shown within the universal set S. You can choose from 16
different subsets of S. Your subset will then be shaded on the
Venn
diagram.
- Let's
Make a Deal. The classic Monty Hall problem - should I stick
or switch?
- Buffon's
Needle Problem. In playing this old classic you can
estimate
the value of pi.
- Pass the Pig.
A game in which "pigs" are tossed and a score is given as to how they
land.