I wish I can like this video one trillion times. Thank you for opening up my brain, this is what I call context-based comprehensible explanation (instruction).
I'm wondering if it is necessary to run this particular function if the same info had been noted on the data when running other functions. I guess it depends on the research question and the importance/significance of the outlier?
Dear Dr. Grande, I am applying a 22 items SERVQUAL scale on a 5 points Likert scale to study five dimensions of service quality in higher education. My sample is from Private Higher Education institutions which comprises 79 cases. Before I dealt with outliers, I performed normality tests, my data was not normally distributed according to both KS and Shapiro. I also am required to perform an exploratory factor analysis to examine the validity of the scale. My question to you, do I need to deal with outliers for the 22 items before or after the exploratory factor analysis?
Would censoring the extreme outliers be a valid approach? If using bootstrap, do these extreme values still present the same problem? Thank you for this wonderful series!
Dr. Grant, I have outliers in all my scales: WRB (1); PRB (9) + (1 Extreme); VI (4); DE (3); and AB (5) + (1 Extreme). I have the reports with the interquartile ranges and have calculated the min. and max. scores for each one. What is my next step?
Why when apply the IQR on excel I get different result than SPSS ?? ( hence: I used both 1.5 & 3 as multipliers) to observe the extreme and low outliers but I don’t get the same results. I used Q1, Q2 and IQR values from SPSS. Moreover, excel doesn’t accept a big dataset for the QUARTILE function
I wish I can like this video one trillion times. Thank you for opening up my brain, this is what I call context-based comprehensible explanation (instruction).
Box plots have seemed straightforward in checking for outliers, but this clearly explained how outliers may be calculated. Thanks.
Your work is marvellous and very assistiev to us Sir, live long and happy
Very well explained! Thank you very much! Keep safe & happy!
Thanks for sharing Dr. Grande. Do you have a reference that justifies using this method?
I'm wondering if it is necessary to run this particular function if the same info had been noted on the data when running other functions. I guess it depends on the research question and the importance/significance of the outlier?
Dear Dr. Grande,
I am applying a 22 items SERVQUAL scale on a 5 points Likert scale to study five dimensions of service quality in higher education. My sample is from Private Higher Education institutions which comprises 79 cases. Before I dealt with outliers, I performed normality tests, my data was not normally distributed according to both KS and Shapiro. I also am required to perform an exploratory factor analysis to examine the validity of the scale.
My question to you, do I need to deal with outliers for the 22 items before or after the exploratory factor analysis?
Would censoring the extreme outliers be a valid approach? If using bootstrap, do these extreme values still present the same problem? Thank you for this wonderful series!
What happens when the bottom whisker is lower than the minimum obtainable score OR the top whisker is higher than the maximum obtainable score??
How to understand the descriptives and extreme values chart of outliers analysis in spss?
Dr. Grant, I have outliers in all my scales: WRB (1); PRB (9) + (1 Extreme); VI (4); DE (3); and AB (5) + (1 Extreme). I have the reports with the interquartile ranges and have calculated the min. and max. scores for each one. What is my next step?
Thanks for sharing Dr. Grande :)
Why when apply the IQR on excel I get different result than SPSS ?? ( hence: I used both 1.5 & 3 as multipliers) to observe the extreme and low outliers but I don’t get the same results. I used Q1, Q2 and IQR values from SPSS. Moreover, excel doesn’t accept a big dataset for the QUARTILE function
hi can you show an example of write up for boxplot
or share any guidelines on write up
@DrToddGrande includes on write up for ouliers and the reason we have corrected or not corrected it
Great video!
Can we use quartiles if data are non normal distributed ?
Sam Kab hi Sam I think that what he was doing the whole time . His data was not normalized
Great video! Thank you!
You're welcome!
very good, but even on double speed you sound half speed...