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What's New in the Interactive Statistical Pages

Explorer -- A data exploration / graphing / analysis program with a very elegant drag-and-drop interface.  Accepts data from text files, Excel spreadsheet, MySQL databases, and copy/pasted from the clipboard. Provides over a dozen kinds of plots and diagrams, basic statistical summaries, significance tests (chi-square, t, ANOVA ) and more advanced analyses (factorial, principal components, discriminant, variance, linear regression). Executable programs can be downloaded for Windows and Mac OSX. Written in JavaScript, so it can also be run in any modern browser. See a short demo here.  (added 10/08/2015)
MATLAB tutorial -- covers setting it up,  interactive mode and script files, writing Matlab code (variables, arrays and matrices, control flow and classes), and sample applications. (added 09/18/2015)

HealthCareSpanish -- a web site to help you learn common phrases and medical terms in Spanish. (added 09/18/2015)

AppOnFly has a different approach -- the company maintains Windows computers with a wide selection of Windows software, including utilities for accessing PDF, ZIP, graphics and other files, web browsers, various office suites (MS Office, Libre Office, Apache OpenOffice, WordPerfect Office), and statistical packages (SPSS,  NCSS, R), to mention a few. They then provide apps for accessing this Windows desktop environment from any device -- computer, smartphone, tablet (Windows, Mac OS, iOS, Android). This is a pay-for service, but they offer one-month free trials.

A Guide to Not-for-Profit Online Universities - a guidebook to help new and returning students understand the online academic landscape and how best to succeed in an online degree program. Key elements of the guide include:
- A comprehensive review of the growth of distance education at not-for-profit universities
- Differences between for-profit and not-for profit online schools
- An exploration of the most popular online learning platforms
- Scholarships and other financial aid options for online students   (added 08/20/2015)

Sample size calculator for pilot or safety studies where the goal is to detect the occurrence of one or more events that might indicate possible problems in study design (ambiguous inclusion criteria, misinterpretation of questionnaire items) or product safety (occurrence of serious adverse events, abnormal lab tests, or other safety markers). Enter the prevalence rate you want to be able to detect (like one in a hundred), and the probabibility you want to have of seeing at least one such event in your sample (like 95% probability), and the page will tell you how many subjects you need in the study. (added 08/05/2015)

JASP -- a new package (still in "beta" development) that's described by the authors as a "low-fat alternative to SPSS", and "Bayesian statistics made accessible". Provides a user-friendly interface to many of the commonly-used statistical analyses -- descriptive statistics, plots, t tests, Leveneís Test, ANOVA, ANCOVA, contingency tables, Pearson and Spearman correlation, Kendallís Tau-B, and linear regression. For many of these analyses, the JASP also provides the closest corresponding Bayesian equivalent, implemented in a way that will be understandable to people not familiar with Bayesian concepts and terminology. (added 07/29/2015)
Statigraphics Stratus -- a browser-based version of Stratigraphics statistical software. Provides plotting, probability distributions, summary statistics, one-, two-, and multiple-sample analysis, time-series analysis, regression analysis, curve-fitting, attribute estimates, ANOVAs, Statistical Process Control, smoothing, power/sample-size calculations, and other statistical analyses.Also provides  access to over 50 applets in which you can enter data, compute statistics, create tables and graphs, and print out the results. The free "Guest" version supports up to 100 rows and 10 columns of data. For larger data sets, a single-user copy or a corporate deployment license can be purchased. To use the Guest version, click here.  (added 07/18/2015)

How to Test a Random Number Generator -- a chapter from the book Beautiful Testing, by John D. Cook. (added 07/15/2015) -- 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)

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