# One Numerical Variable

• ### DAU StatRefresher: Expectations

This interactive tutorial on Expectations helps students understand the concept of expectations, recognize and use variance and standard deviation, understand the method of moments, recognize and use co-variance, and solve exercise problems using expectations.
• ### DAU StatRefresher: Linear Regression

This interactive tutorial on Linear Regression helps the user understand the definition of linear regression, understand the meaning of correlation, use scatter plots, recognize and calculate errors in linear regression, use simple linear regression analysis, use residual analysis of the regression equation, understand the significance of the correlation coefficient and the regression coefficient in linear regression, and solve exercise problems using linear regression.
• ### DAU StatRefresher: Data Analysis

This is an interactive tutorial on Data Analysis topics including representations of data, understand the definition of mean, understand the definition of variance, recognize a few other useful concepts, recognize various sampling techniques, and solve exercise problems using data analysis.
• ### Video: Against All Odds: 17. Samples and Surveys

This free online video program "shows how to improve the accuracy of a survey by using stratified random sampling and how to avoid sampling errors such as bias. While surveys are becoming increasingly important tools in shaping public policy, a 1936 Gallup poll provides a striking illustration of the perils of undercoverage."
• ### Normal Distribution JAVA Applet

This applet shows the normal or Gaussian distribution. The distribution has two parameters, the mean and the standard deviation. Click the draw button after filling in new values for the mean and the standard deviation to obtain a new diagram of the normal distribution.

• ### Data Collection: Data Cleaning Assignment

This activity guides students through the process of checking the validity of data, performing summary analysis, constructing box plots, and determining whether significant differences exist. The data comes from a study of mineral levels in older adults and is available in Minitab, Excel, SAS, and text formats.
• ### ** Introduction to Minitab

This laboratory introduces students to the basics of the Minitab software. Students make use of a basic example (water consumption and temperature) to introduce students to manipulation of data, calculation of descriptive statistics, creation of histograms, boxplots and scatterplots. Students are asked to hand in the results they have produced. Accompanying documents give model solutions.
• ### Analysis Tool: Statistics Online Computational Resources (SOCR)

This applets on this site include: interactive graphs of many distribution models; a collection of computer generated games; a collection of data modeling aids including curve fitting, wavelets, matrix manipulations, etc.; p-values, quantiles & tail-probabilities calculations; virtual online probability experiments and demonstrations; and a large collection of statistical techniques for online data analysis, visualization, and integration.

• ### Virtual Statistician

This site contains lessons which include steps, examples, and a calculator, on standard deviation, Pearson's r, t-test, one-way ANOVA, and Tukey's Post Hoc Test.
• ### Average, Standard Deviation and Relative Standard Deviation

This pdf file gives definitions for average, standard deviation, and relative standard deviation, and works through a short problem as an example.