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What's New in the Interactive Statistical Pages -- an easy-to-use curve-fitting page.  Offers 13 pre-defined functions (no initial guesses required), along with the ability to fit a general non-linear function you provide (along with initial guesses). Displays the results graphically, along with the formula of the fitted curve. Several  types of unequal data-point weighting are provided. Lets you generate predicted values (interpolated and extrapolated) from the fitted curve. Lets you save results in Excel and PDF formats. (added 03/13/2015)

MaxStat statistics & graphics program (for Windows): Easy to use, modern interface -- specify an analysis in three simple steps within a single dialog.  (added 02/13/2015)
Two versions are available:
  *  Lite (free) has descriptive statistics, hypothesis testing (t-tests, chi-square, 1-way ANOVA with post-hocs, non-parametric tests), distribution testing, linear regression,  correlation, many basic types of graphs; limited to 254 rows and 12 columns of data, no import/export.
  *  Professional  (free 30-day trial) advanced analyses (unlimited rows & columns, import/export, many more analyses (2-way ANOVA, logistic and non-linear regression, principal-components analysis and multidimensional scaling, time series, power/sample-size, factorial design), more graph types, word-processing and formatting of results.  (added 02/08/2015)

Kaplan-Meier Survival Plot -- for one or more groups. Draws K-M curves with optional confidence bands (ordinary, log, or log-log type, at the 50, 80, 90, or 95% conf. level). This is part of  Peter Rosenmai's EurekaStatistics web site (a blog about statistics and R). (added 01/26/2015)

Two HTML5 web pages by  Robert Mening:
   Beginner's guide to HTML5 - Includes a handy "HTML5 Cheat Sheet".
   HTML5 Periodic Table - a clever interactive reference to the components of HTML5. (added 01/26/2015)

One-way Analysis of Variance from Summary Data web page has finally (after 10 years!) been updated to perform the Tukey HSD post-hoc test. This page does not require individual data measurements, only the count, mean, and standard deviation (or standard error of the mean) for each group. (added 12/21/2014)

Data Desk -- first released in 1986, is one of the oldest Mac programs still actively developed. The modern versions (for Mac OS X and Windows computers) are available for sale from Data Description, Inc. But in honor of its origin, there is also a free version that runs on Macintosh 680x0 computers (which were made from 1984 to 1996).  While this old hardware is now ancient history, there are software emulators of 680x0 computers that run on modern Mac, Windows and Linux computers (see the Gryphel Project). (added 12/21/2014)

Number Needed to Treat (NTT) Calculator -- you enter the risk of outcome for the treated and control groups, and this page will calculate the absolute risk reduction (ARR), relative risk (RR), relative risk reduction (RRR), and number needed to treat (NNT). This page also contains a handy table showing NNT for various values of control group risk and relative risk, and a chart illustrating the relationship. (added 11/06/2014)

Affordable Colleges Online -- provides free higher education tools and information for current and future college students and their families. Focusing mainly on the not-for-profit programs, this site provides guidebooks for veterans, students with disabilities, Hispanic students, and other college hopefuls; an in-depth financial aid section with articles, guides, expert Q&As, and walkthroughs of key processes and forms; an expert-driven, 20-page guide to online learning success; and a directory of introductory Massive Open Online Courses (MOOCs) from top universities. (added 10/18/2014)   The web site contains a Graduate Degree Guidebook to Online Masters Programs that discusses online master's degrees and program options, and includes helpful information regarding accreditation, time expectations and deadlines, and other frequently asked questions. (added 11/06/2014)

Guide to College Internships -- a student's guide to skillfully locating, bargaining and accepting Internships.  Part of the web site, which also contains several other guides, lists of colleges and online degrees, and several rankings of colleges by net price, selectivity, and graduation rates. (added 10/09/2014)

Online MBA Programs -- part of the Affordable Colleges Online web site. MBA career guide tailored to the needs of current and future MBA students. The guide includes several key sections, including industry resources, career path outlines, supplemental free online courses, an MBA specialization matrix, and moreThe developers of this page worked with two career counselors and an MBA student to create this content with the intention of providing actionable, relevant, and timely information. (added 10/08/2014)

a very polished calculator for two-group Student t test, with graphical display of means and confidence intervals, and an interpretation of the results. Can take individual values or summary statistics (N, mean, SD) for each group. (added 10/04/2014)

Comparison of two proportions between two groups (each given as # successes / # of trials). Shows confidence intervals, and interprets the results of the comparison. (added 10/04/2014)

a very polished calculator for comparing two event rates (number of events in a certain amount of time). Shows confidence intervals around each event rate, and interprets the significance of the difference between the rates of the two groups. (added 10/04/2014)

Kaplan-Meier Survival Plot and LogRank -- calculates survival curves (with confidence bands), and performs a LogRank test test to  comparing survival curves between two groups. (added 10/04/2014)

Compare Average Survival Time between two distributions -- Enter the number of events and the average time to event for each of two groups. The calculator will display the confidence interval around each mean time, and will compare the two mean times. (Assumes an exponential-shaped survival curve.) (added 10/04/2014)
Required sample size for comparing proportions between two groups (added 10/04/2014)

Wizard -- (for Macintosh only), provides all basic statistical tests, emphasizes easy-to-understand, graphically-based results. Imports data from text files, spreadsheets, SQL databases,  and R workspaces (the Pro version can also import SAS, Stata and SPSS files). The free trial versions (standard or Pro versions) never expire; they don't provide p values, or export/save. (added 10/04/2014)

Affordable Online Colleges in America: Rankings & Report -- Edudemic's web site provides information about the most affordable colleges online today. 180 online colleges are ranked on student value, price, and reputation, to determine objectively how far a dollar takes you at each one. These colleges had the best balance of low tuition and stellar performance metrics. (added 09/20/2014)

HTML for Beginners -- A nice introduction to HTML, describing the concept of markup tags, preparing an HTML document, using meta-tags, basic formatting, hyperlinks and anchors, images, forms and tables. It also contains links to other HTML resources. Thanks to the young web designers at the W. B. Goodwin Community Center for suggesting this resource!  (added 07/23/2014)

RegressIt - An Excel add-in for teaching and applied work.  Performs multivariate descriptive analysis and ordinary linear regression.  .  Creates presentation-quality charts in native editable Excel format, intelligently formatted tables, high quality scatterplot matrices, parallel time series plots of many variables, summary statistics, and correlation matrices.   Easily explore variations on models, apply nonlinear and time transformations to variables, test model assumptions, and  generate out-of-sample forecasts.   Includes audit trail and organization features: output stored in separate worksheets, date/time/username worksheet stamps, unique model names in all table and chart titles, and an additional worksheet with side-by-side comparisons of models. (added 05/23/2014)

Develve -- stats package for fast and easy interpretation of experimental data in science and R&D in a technical environment. Everything is directly accessible and  results are directly visible, with no hidden menus; e.g.:  graphs are easily scrollable, and when clicked, a bigger version pops up. Results for group comparisons directly indicate the significance of the difference in average and variation, and if the sample size is sufficiently large. Has a basic mode for statistical testing, and a design-of-experiments mode. (added to Free Software page on 03/27/2014)

 ID Hunter -- a comprehensive listing of online graduate certificates in instructional design, online teaching, e-learning, and related fields, along with info on credit hours required, costs, application requirements, and related master’s programs. The website is free to use and requires no registration. (added to Other Links page on 03/27/2014)

Diagnostic Test Evaluation -- From a 2x2 cross-tab of diagnostic test results (positive or negative) vs. true disease state (present or absent), calculates sensitivity, specificity, positive and negative likelihood ratios and predictive values, and disease prevalence, along with their 95% confidence intervals. (added 03/06/2014)

Textbook rental for the duration of a course can save you 80 to 90% of the cost of buying the textbook outright. (added 02/25/2014)

An interactive homework-tutoring system for math (including algebra, geometry, trigonometry, calculus, probability and statistics). A paid service, but there's a 7-day free trial. (added 02/25/2014)

Check out the web site, which contains (at last count) 19 interactive calculators for power or  required sample size for many different types of statistical tests: testing 1 mean, comparing 2 or more means, testing 1 proportion, comparing 2 or more proportions, testing odds ratios, and two 1-sample tests (normal and binomial-based). This site also provides calculators for non-inferiority and equivalence studies. The web pages display graphs that dynamically show how power varies with various design parameters as you change other parameters. (added 02/18/2014)

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