Move over video games and sports. Make room for escape rooms. This burgeoning form of entertainment found its roots in the video gaming movement. Escape rooms tap into a player's drive to reach the next level, solve a puzzle and win. Escape rooms present a physical game that traps you
A previous article describes the DFBETAS statistics for detecting influential observations, where "influential" means that if you delete the observation and refit the model, the estimates for the regression coefficients change substantially. Of course, there are other statistics that you could use to measure influence. Two popular ones are the
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As a data scientist, did you ever come to the point where you felt the need for an evolved analytics platform bringing together the disparate skills of open source and commercial software? A system that can enable advanced analytic capabilities. This is now possible and easy to implement. With many
What is Item Response Theory? Item Response Theory (IRT) is a way to analyze responses to tests or questionnaires with the goal of improving measurement accuracy and reliability. A common application is in testing a student’s ability or knowledge. Today, all major psychological and educational tests are built using IRT.
Sometimes when I am setting up, or helping someone setup, identity synchronisation between the SAS® platform and Microsoft Active Directory (AD), I run into SSL/TLS certificate validation issues. I am usually using Metacoda Identity Sync, but it c...
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varname = compress(varname, , 'kw');The modifier “k” stands for ‘KEEP’ and the modifier “w” stands for ‘WRITABLE’. When compress function is used in combination of K & W modifiers, it keeps all the writable characters which means it deletes all the...
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My article about deletion diagnostics investigated how influential an observation is to a least squares regression model. In other words, if you delete the i_th observation and refit the model, what happens to the statistics for the model? SAS regression procedures provide many tables and graphs that enable you to
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When you install Metacoda Custom Tasks for use in SAS® Enterprise Guide® and the SAS® Add-In for Microsoft Office you may find you don’t see the new menu items you expected in the Tools menu: There are 2 main reasons why they may be missing: 1) t...
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For linear regression models, there is a class of statistics that I call deletion diagnostics or leave-one-out statistics. These observation-wise statistics address the question, "If I delete the i_th observation and refit the model, what happens to the statistics for the model?" For example: The PRESS statistic is similar to
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