what is \bar{x} and \tidle{x}?

[timm]

what is \bar{x} and \tidle{x}?

[WilliamNichols]

Possibly, what was the source? It looks like a survey and I’ve seldom approved of using means and standard deviations on ordinal scales. (it can be done, but I seldom see it done correctly.

From: Tim Menzies [mailto:[email protected]]
Sent: Saturday, August 01, 2015 7:46 AM
To: ai-se/phaseDelay [email protected]
Subject: [phaseDelay] what is \bar{x} and \tidle{x}? (#23)

mean and standard deviation?

[image]https://cloud.githubusercontent.com/assets/29195/9021737/3b65e6ec-3821-11e5-8e63-ab60c30be041.png

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[llayman]

Yes, they are means and standard deviations. Should I just use median?

[WilliamNichols]

I worked with a guy who did survey instruments in Northwestern and Minnesota Poly Sci departments. He always recommended using medians and modes for Likert scale questions unless you aggregate a number of questions. That leaves some issues of scale, but aggregating the ranked ordinals from different questions to create a ratio value was accepted. Standard deviations with hard 1-5 bounds typically aren’t very helpful. Interquartile range or other non-parametric makes more mathematic sense. It’s also important to be clear if the data is mounded or double peaked.

From: Lucas Layman [mailto:[email protected]]
Sent: Monday, August 17, 2015 12:37 PM
To: ai-se/phaseDelay
Cc: William Nichols
Subject: Re: [phaseDelay] what is \bar{x} and \tidle{x}? (#23)

Yes, they are means and standard deviations. Should I just use median?

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