SEM The Musical 12.5


We will be performing SEM The Musical 12.5 this upcoming Thursday, November 29. Why the designation "12.5"? For roughly the last dozen years, SEM had been the fourth course in our HDFS graduate statistics sequence (after Intro, ANOVA/Regression, and Multivariate) and always taught in the spring. However, we revamped the statistics sequence, knocking out the Multivariate course, moving SEM to third in the order, and adding Longitudinal in the fourth position. Starting with the current semester, SEM is now a fall course. Because only six months (rather than 12) have elapsed since the last SEM Musical, we are  therefore referring to the upcoming one as 12.5.

As always, we'll sing some new songs (shown below) and some classics of the previous 12 years. Just click on any of the following numbers to access a prior musical: 123456789101112.

Todd Little Parcels Indicators
Lyrics by Alan Reifman
(May be sung to the tune of “[My Baby Does the] Hanky Panky,” Greenwich/Barry, popularized by Tommy James & the Shondells)
[Video of performance; added 12/4/2018]

Todd Little parcels indicators,
Todd Little parcels indicators,
He’s one of modeling’s innovators,
He checks residuals’ “correlators*,”
Todd Little parcels indicators...

Todd Little parcels indicators,
Todd Little parcels indicators,
He’s one of modeling’s innovators,
He checks residuals’ “correlators,”
Todd Little parcels indicators...

You’ve got a bunch of indicators, you know,
You have to decide, how they’re gonna go,
Should you combine them, into smaller sets?
Do so at random or with other intent?
They’re still debating, yeah they’re still debating...

Todd Little parcels indicators,
Todd Little parcels indicators,
He’s one of modeling’s innovators,
He checks residuals’ “correlators,”
Todd Little parcels indicators...

(Guitar solo)

You’ve got a bunch of indicators, you know,
You have to decide, how they’re gonna go,
Should you combine them, into smaller sets?
Do so at random or with other intent?
They’re still debating, yeah they’re still debating...

Todd Little parcels indicators,
Todd Little parcels indicators,
He’s one of modeling’s innovators,
He checks residuals’ “correlators,”
Todd Little parcels indicators...

He’s one of modeling’s innovators,
He checks residuals’ “correlators,”
Todd Little parcels indicators ,
Todd Little parcels indicators... (fade out)

---
*There is, of course, no such term as “correlator.” I made it up to maintain the rhyme. What I’m referring to is how one may choose to combine into a parcel indicators that, while initially separate, show a residual correlation. Little et al. (2013, “Why the items versus parcels controversy needn’t be one,” Psychological Methods) note that: “...when a correlated residual is evident in an item-level solution, the most advantageous parcel solution may be one that aggregates those correlated items together” (p. 290).


Oh Mplus!
Lyrics by Alan Reifman
(May be sung to the tune of “Holy War,” Lukather/Vanston/Williams for Toto)
[Video of performance; added 12/18/2018]

(Guitar riff four times)

So, you need, some new, S-E-M software,
From lots of options, you can choose,
I’d say use AMOS, for the basics,
But Mplus, when things, are abstruse,

Ready, to start,
Your data, must,
Be in plain-text,
With no labels on top,

Run it, run it,
Then check, warnings,
So you can make sure,
That your run, didn’t stop,

For more, advanced stuff,
Check out all, the working papers,
Things should, be clear, eventually,

Oh Mplus!
Yes, you’re such a quirky program,
Adding covs, for which no one asked,
You’ve got quite, a learning curve,
To master, all the details,
It is a, substantial task!

(Guitar riffs twice)

Now, if you want latent classes,
Or, multilevel modeling,
Mplus keeps updating, its routines,
So it has got, the things you need,

You can get help,
In figuring, out, the details,
A book by Geiser’s, crystal clear,

There also is,
A website, to help you,
Where they do, Q & A,

Give it a try,
But don’t lose, your patience,
It takes some time, to find your way,

Oh Mplus!
Yes, you’re such a quirky program,
Adding covs, for which no one asked,
You’ve got quite, a learning curve,
To master, all the details,
It is a, substantial task!

(Guitar solos)

Oh Mplus!
Yes, you’re such a quirky program,
Adding covs, for which no one asked,
You’ve got quite, a learning curve,
To master, all the details,
It is a substantial task!

Oh Mplus!
Yes, you’re such a quirky program,
Adding covs, for which no one asked,
You’ve got quite, a learning curve,
To master, all the details,
It is a substantial task!