This PowerPoint presentation discusses observational studies in relation to meta-analysis. It covers why they are used, bias, and other topics.
This PowerPoint presentation discusses observational studies in relation to meta-analysis. It covers why they are used, bias, and other topics.
This presentation on data analysis addresses observational studies and randomized controlled trials in two different sections. Types of studies are defined and examples of each study is given to emphasize the differences. Factors and variables are also discussed.
This site describes numerous methods of nonprobability sampling, including accidental, haphazard or convenience sampling and the many types of purposive methods.
This applet simulates rolling dice and displays the outcomes in a histogram. Students can choose to roll 1, 2, 6, or 9 dice either 1, 10, 20, or 100 times. The outcome studied is the sum of the dice and a red line is drawn on the histogram to show expected number of occurences of each outcome.
This applet from Statistical Java allows the user to generate bivariate data for analysis with simple linear regression. The page describes the equations used to generate the data and estimate the regression lines. Users manipulate data generated and create their own line of best fit to try and match the computer generated regression line. This page was formerly located at http://www.stat.vt.edu/~sundar/java/applets/Regression.html
EasyCharts is a complete library of java chart components, chart applets, and chart servlets that enable programmers to add charts and graphs in java applications, web applications, and web pages with just a few lines of code. The java chart library includes bar charts, line charts, and pie charts and is highly configurable. The java chart library supports charts with multiple data series, overlay charts, drilldown charts, and interactive features such as zooming and scrolling of chart data.
This library contains a plethera of downloadable applets and the components of the applets for use by teachers and students of probability and statistics. These objects (both executable files and source code) can be downloaded, modified if desired, and reused.
This applet, for which the source code is available, lets you mark the locations of ordered pairs, (x, y), on the left screen, and then the applet determines the equation of the regression line and graphs it. The applet will also show confidence bands for means of y corresponding to a given x, and prediction bands for future values of y corresponding to a given value x. Note: the applet opens in a seperate window when you open the webpage.
In this free online video program, "students will discover how to convert the standard normal and use the standard deviation; how to use a table of areas to compute relative frequencies; how to find any percentile; and how a computer creates a normal quartile plot to determine whether a distribution is normal. Vehicle emissions standards and medical studies of cholesterol provide real-life examples."
The Food and Drug Administration requires pharmaceutical companies to establish a shelf life for all new drug products through a stability analysis. This is done to ensure the quality of the drug taken by an individual is within established levels. The purpose of this out-of-class project or in-class example is to determine the shelf life of a new drug. This is done through using simple linear regression models and correctly interpreting confidence and prediction intervals. An Excel spreadsheet and SAS program are given to help perform the analysis. Key words: prediction interval, confidence interval, stability