sample size

Member Training: Model Building Approaches

January 1st, 2019 by

There is a bit of art and experience to model building. You need to build a model to answer your research question but how do you build a statistical model when there are no instructions in the box? 

Should you start with all your predictors or look at each one separately? Do you always take out non-significant variables and do you always leave in significant ones?

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Member Training: Power Analysis and Sample Size Determination Using Simulation

July 30th, 2018 by
This webinar will show you strategies and steps for using simulations to estimate sample size and power. You will learn:
  • A review of basic concepts of statistical power and effect size
  • A simulation-based approach to power analysis
  • An overview of how to implement simulations in various popular software programs.

Four Common Misconceptions in Exploratory Factor Analysis

June 5th, 2018 by

Today, I would like to briefly describe four misconceptions that I feel are commonly perceived by novice researchers in Exploratory Factor Analysis:

Misconception 1: The choice between component and common factor extraction procedures is not so important.

In Principal Component Analysis, a set of variables is transformed into a smaller set of linear composites known as components. This method of analysis is essentially a method for data reduction.

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Member Training: The Fundamentals of Sample Size Calculations

May 28th, 2018 by

Sample size estimates are one of those data analysis tasks that look straightforward, but once you try to do one, make you want to bang your head against the computer in frustration. Or, maybe that’s just me.

Regardless of how they make you feel, they are super important to do for your study before you collect the data.

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Member Training: Statistical Rules of Thumb: Essential Practices or Urban Myths?

March 1st, 2017 by

There are many rules of thumb in statistical analysis that make decision making and understanding results much easier.

Have you ever stopped to wonder where these rules came from, let alone if there is any scientific basis for them? Is there logic behind these rules, or is it propagation of urban legends?

In this webinar, we’ll explore and question the origins, justifications, and some of the most common rules of thumb in statistical analysis, like:

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Five things you need to know before learning Structural Equation Modeling

March 14th, 2016 by

By Manolo Romero Escobar

If you already know the principles of general linear modeling (GLM) you are on the right path to understand Structural Equation Modeling (SEM).

As you could see from my previous post, SEM offers the flexibility of adding paths between predictors in a way that would take you several GLM models and still leave you with unanswered questions.

It also helps you use latent variables (as you will see in future posts).

GLM is just one of the pieces of the puzzle to fit SEM to your data. You also need to have an understanding of:
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