Comparison of assessments | Statistical reliability | Statistical tests | Covariance and correlation

Item-total correlation

The item-total correlation test arises in psychometrics in contexts where a number of tests or questions are given to an individual and where the problem is to construct a useful single quantity for each individual that can be used to compare that individual with others in a given population. The test is used to see if any of the tests or questions ("items") do not have responses that vary in line with those for other tests across the population. The summary measure would be an average of some form, weighted where necessary, and the item-correlation test is used to decide whether or not responses to a given test should be included in the set being averaged. In some fields of application such a summary measure is called a scale. (Wikipedia).

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RELATIONSHIPS Between Variables: Standardized Covariance (7-1)

Correlation is a way of measuring the extent to which two variables are related. The term correlation is synonymous with “relationship.” Variables are related when changes in one variable are consistently associated with changes in another variable. Dr. Daniel reviews Variance, Covariance,

From playlist Correlation And Regression in Statistics (WK 07 - QBA 237)

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Correlation Coefficient

This video explains how to find the correlation coefficient which describes the strength of the linear relationship between two variables x and y. My Website: https://www.video-tutor.net Patreon: https://www.patreon.com/MathScienceTutor Amazon Store: https://www.amazon.com/shop/theorga

From playlist Statistics

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Covariance (12 of 17) Covariance Matrix wth 3 Data Sets and Correlation Coefficients

Visit http://ilectureonline.com for more math and science lectures! To donate:a http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 We will find the correlation coefficients of the 3 data sets form the previous 2 videos. Next video in this series can be seen at:

From playlist COVARIANCE AND VARIANCE

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Covariance Definition and Example

What is covariance? How do I find it? Step by step example of a solved covariance problem for a sample, along with an explanation of what the results mean and how it compares to correlation. 00:00 Overview 03:01 Positive, Negative, Zero Correlation 03:19 Covariance for a Sample Example

From playlist Correlation

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Covariance (8 of 17) What is the Correlation Coefficient?

Visit http://ilectureonline.com for more math and science lectures! To donate:a http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 We will learn what is and how to find the correlation coefficient of 2 data sets and see how it corresponds to the graph of the data

From playlist COVARIANCE AND VARIANCE

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Covariance (9 of 17) What is the Correlation Coefficient?

Visit http://ilectureonline.com for more math and science lectures! To donate:a http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 We will calculate the correlation coefficients of 2 separate 2 data sets and graph the 2 graphs and see how the graphs corresponds t

From playlist COVARIANCE AND VARIANCE

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EFFECT Size for Correlation: Coefficient of Determination (7-3)

The Correlation Coefficient is also an Effect Size. An r value can be squared to calculate an effect size. The r-squared is the Coefficient of Determination, expressing the proportion of variance in the dependent variable (Y) explained by variance in the independent variable (X). The rever

From playlist Correlation And Regression in Statistics (WK 07 - QBA 237)

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Covariance (1 of 17) What is Covariance? in Relation to Variance and Correlation

Visit http://ilectureonline.com for more math and science lectures! To donate:a http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 We will learn the difference between the variance and the covariance. A variance (s^2) is a measure of how spread out the numbers of

From playlist COVARIANCE AND VARIANCE

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Conceptual Questions about Correlation

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Conceptual Questions about Correlation

From playlist Statistics

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JASP/Excel - Exploratory Factor Analysis Example

Lecturer: Dr. Erin M. Buchanan Missouri State University Spring 2017 This video covers EFA lecture and procedures including the following walk through: 1) Data screening in Excel 2) EFA in JASP with comments on the numbers of factors, rotations, loadings, simple structure, and fit indice

From playlist Learn and Use G*Power

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Cronbach's α and McDonald’s ω reliability coefficients in Jamovi | Theory and practice

This video is bout Cronbach's α and McDonald’s ω in Jamovi. Useful links: Jamovi: https://www.jamovi.org/download.html Two book chapters: https://www.routledge.com/Quantitative-Data-Analysis-for-Language-Assessment-Volume-I-Fundamental/Aryadoust-Raquel/p/book/9780367671396 Paper by Haye

From playlist Jamovi software

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SPSS Tutorial for data analysis | SPSS for Beginners | Part 2

SPSS Statistics is a software package used for interactive, or batched, statistical analysis. Long produced by SPSS Inc., it was acquired by IBM in 2009. The current versions are named IBM SPSS Statistics. In this course you will how to use SPSS for data analysis. This #SPSS course is begi

From playlist SPSS data Analysis

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R - Exploratory Factor Analysis Lecture

Lecturer: Dr. Erin M. Buchanan Fall 2020 https://www.patreon.com/statisticsofdoom This video is part of my structural equation modeling class - you will learn how to perform an exploratory factor analysis as a way to ease into the ideas of SEM. You will learn how to assess the number of

From playlist Structural Equation Modeling 2020

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R & Python - Exploratory Factor Analysis

Lecturer: Dr. Erin M. Buchanan Summer 2020 https://www.patreon.com/statisticsofdoom This video is part of my human language modeling class - this video set covers the updated version with both R and Python. Expanding on cluster analysis, this video examines how to put together concepts

From playlist Human Language (ANLY 540)

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R - Register Variation with Exploratory Factor Analysis

Lecturer: Dr. Erin M. Buchanan Summer 2019 https://www.patreon.com/statisticsofdoom This video is part of my human language modeling class. On our last video, we will cover exploratory factor analysis to capture the dimensional data that words can present. Note: these videos are part of

From playlist Human Language (ANLY 540)

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R - Exploratory Factor Analysis Lecture 1

Lecture materials and assignment available at statisticsofdoom.com. https://statisticsofdoom.com/page/graduate-statistics/ Used in the following courses: Graduate Statistics

From playlist Advanced Statistics Videos

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R - Exploratory Factor Analysis Lecture & Example

Lecturer: Dr. Erin M. Buchanan Missouri State University Spring 2016 This video covers basic theory behind exploratory factor analysis and principle components analysis. A complete example of EFA from data screening through parallel analysis, simple structure, fit indices, reliability, a

From playlist Advanced Statistics Videos

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R - Item Response Theory Analysis Lecture

Lecturer: Dr. Erin M. Buchanan Missouri State University Summer 2016 This lecture covers Item Factor Analysis and Item Response Theory from the Beaujean SEM in R book. IRT information also pulled from StatsCamp materials taught by William Skorupski (highly recommend his class!). Both dic

From playlist Structural Equation Modeling

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Estimate the Correlation Coefficient Given a Scatter Plot

This video explains how to estimate the correlation coefficient given a scatter plot.

From playlist Performing Linear Regression and Correlation

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Reliability 2: Cronbach's alpha and internal reliability

In this video, I discuss Cronbach's alpha and internal reliability. I also demonstrate how to compute Cronbach's alpha in SPSS and make sense of SPSS output such as corrected-item-total correlation, squared multiple correlations, and Cronbach's alpha if item deleted. Taber's (2017) paper c

From playlist Reliability analysis

Related pages

Scale analysis (statistics) | Statistical population