More Issues with P-Values

Hi all!  I just made a new post on StatisticalBullshit.com about p-values.  Use the following link to read more!

https://statisticalbullshit.com/2017/09/25/more-issues-with-p-values/

If you have any specific topics that you’d like to read about, please let me know by emailing MHoward@SouthAlabama.edu.

Identifying Multiple Modes in Excel

Very early in my intro-level statistics courses, I always cover the topics of mean, median, and mode. For any dataset, there can only be a single mean and/or median value, but there can be multiple modes. For some strange reason, the =mode() command in Excel will only provide the first mode that appears in a dataset, even when multiple modes exist! For this reason, I made a guide on how to use the =mode.mult() command. Never again should you incorrectly identify the number of modes in a dataset!

Here is the link: https://mattchoward.com/multiple-modes-in-excel/

Descriptive Statistics in Excel

I just added a page on How to Calculate Descriptive Statistics in Excel to the Excel Statistics Help portion of my Statistics Help page.  If you need help calculating descriptives, click here:

https://mattchoward.com/descriptive-statistics-in-excel/

As always, email me at MHoward@SouthAlabama.edu if you have any questions!

How to Perform a T-Test in Excel

Recently, I added a page on How to Perform a T-Test in Excel to the Excel Statistics Help portion of my Statistics Help page.  So, if you need help performing a t-test in excel, click here:

https://mattchoward.com/how-to-perform-a-t-test-in-excel/

As always, email me at MHoward@SouthAlabama.edu if you have any questions!

A New Website!

On MattCHoward.com, I try to keep the content relevant to my academic work.  That is, most of the pages and posts are either (a) answers to student questions, (b) answers to statistical research questions, (c) or relevant to my current
studies.  I recently realized that MattCHoward.com has little room for content
regarding my consulting experiences.  For this reason, I started the website
StatisticalBullshit.com!

The purpose of StatisticalBullshit.com is to educate readers about
nefarious statistical practices commonly seen in industry – practices that could be costing you thousands…or even millions!  Most of the posts will discuss
business statistical issues, but many topics will also cross-over into research discussions.  For instance, the first post is about p-hacking, which can be used to advance an expensive consulting agenda or successfully publish lackluster
research findings.  So, it does not matter if you are currently in academia or
business, StatisticalBullshit.com should have enjoyable content for everyone.

Testing for Dual Mediation

mediationRecently, I performed a study in which I needed to test for dual mediation – when the
indirect effect of Y on X goes through two mediators
(pictured here).  Whenever I need to test for mediation or moderation of any type, I first go to Hayes’s PROCESS macro for SPSS.  It is easy, and it adheres to most all
current best-practices.  If you don’t have it yet, I STRONGLY suggest that you download it now:  http://www.processmacro.org/index.html .  It has saved me hours (days?) on statistical analyses.

So, I opened up the documentation for PROCESS and I found…that it does not have a model for dual mediation!  Of all things, I would have assumed that PROCESS would be able to test for dual mediation!

I searched online for solutions, and I even referred to mediation textbooks to
devise a formula to test for dual mediation.  After having moderate success, I
finally went back to PROCESS.  Out of frustration, I set the program to test the traditional mediation model (with one mediator), but I included two mediators in the dialogue window.  And what did I see?  It provided output for dual mediation!

While this information may not be groundbreaking, it certainly helped me.  I hope that it can also help someone who is as frustrated with dual mediation as I was.  The permanent page for dual mediation testing can be found here:  Testing for Dual Mediation .

If you need any help running dual mediation in process (or any other statistical questions), feel free to email me at MHoward@SouthAlabama.edu.  I always
enjoy hearing from people running interesting statistics!

Commonly Used Survey Scales

It’s been awhile since I’ve made a blog post, but I am consistently updating my website.  So, I thought I’d make a quick post about the section that I update the most:  the List of Commonly Used Scales from the Statistical Help section of my website.

This page includes popular scales taken from academic articles.  Most of these prior articles have demonstrated sufficient psychometric properties and validity information regarding the scale, which means that most reviewers and
practitioners would probably be accepting of their use.

The link to the List of Commonly Used Scales can be found here:  https://mattchoward.com/list-of-scales/ .

If you have any questions about the application of these scales, feel free to email me at MHoward@SouthAlabama.edu.