Estimation Problems in Mplus

Mplus error messages can be confusing for beginners. QuantFish instructor Dr. Christian Geiser shows several examples of estimation problems, discusses potential causes, and walks you through some troubleshooting steps.
#Mplus #Mplusforbeginners #Mpluserror #statistics #CFA #SEM #convergence #identification
FREE weekly stats tips: mailchi.mp/goq...
FREE statistics workshops: www.goquantfis...
Get Dr. Geiser's FREE MPLUS PATH ANALYSIS & MEDIATION MINI-COURSE:
www.goquantfis...
FREE MPLUS SAMPLE SIZE PLANNING & POWER ANALYSIS MINI-COURSE: www.goquantfis...
MPLUS SEM FOR BEGINNERS COURSE: www.goquantfis...
Dr. Geiser's BOOKS:
****Longitudinal Structural Equation Modeling with Mplus: amzn.to/3ekOLOW
****Data Analysis with Mplus: amzn.to/3eg9vY4
ON-DEMAND MPLUS COURSES:
****Mplus from Scratch: www.goquantfis...
****Multilevel Modeling with Mplus: www.goquantfis...
****Latent Class Analysis with Mplus: www.goquantfis...
GET IN TOUCH with DR. GEISER:
****Facebook: / christiangeiserauthor
****Website: christiangeise...
ABOUT THIS INSTRUCTOR:
Dr. Christian Geiser is a quantitative psychologist, author of two books on Mplus, and a leader in the development of latent variable techniques for complex data. With his accessible books and sought-after workshops, he has helped thousands of researchers and students around the world to achieve their analytic goals.
ABOUT QUANTFISH:
We bring top-level stats training from the world's leading methodologists to researchers and students all over the world. Learn more at goquantfish.com.
Some affiliate links may be included at no additional cost to purchasers.

[@Isi-u9d]

Hello and thank you for the great Video!
When I run my CFA I get the following Error Message, which is quite similar to the fist one shown in the video:
THE MODEL ESTIMATION TERMINATED NORMALLY
THE STANDARD ERRORS OF THE MODEL PARAMETER ESTIMATES COULD NOT BE
COMPUTED. THE MODEL MAY NOT BE IDENTIFIED. CHECK YOUR MODEL.
PROBLEM INVOLVING THE FOLLOWING PARAMETER:
Parameter 108, SN BY SN23
THE CONDITION NUMBER IS 0.617D-10.
THE ROBUST CHI-SQUARE COULD NOT BE COMPUTED.
Unfortunately there's only the parameters 1 to 68 in the tech 1 section in the output, so i can't find parameter 108.
I'm a bit lost here. Do you have an idea hot to fix this?

[@QuantFish]

You likely have an underidentification problem. It is difficult to say what the reason is and how this can be fixed without seeing your full model.
Best,
Christian Geiser

[@muhammadqasimshabbir8739]

Dear prof. How we can fix variance instead of fixing one factor loading . Can you write the command here for fixing variance .

[@QuantFish]

Hi Muhammad, Thank you for watching. To free up the first loading (of X1 below) and fix the factor variance of F instead, specify:
F by X1* X2 X3;
F@1;
Best, Christian Geiser

[@MelissaOzsoy]

Lieber Herr Geiser,
vielen Dank für das wirklich hilfreiche Video!
Was kann ich tun, wenn bei mir diese Fehlermeldungauftaucht, wenn ich für Messinvarianznvarianz testen möchte?
Beispiel zur metrischen Invarianz (Skala kwb iwrd durch zwei Items wb01 und wb02 über 3 MZP abgebildet).
model: kwb_1 BY wb01_1
wb02_1(1);

kwb_2 BY wb01_2
wb02_2(1);

kwb_3 BY wb01_3
wb02_3(1);
!Autokorrelation der Fehler der Indikatoren zulassen
wb01_1 WITH wb01_2 wb01_3;
wb01_2 WITH wb01_3;
wb02_1 WITH wb02_2 wb02_3;
wb02_2 WITH wb02_3;
!Der Intercept des ersten Indikators auf 0 fixiert
[wb01_1@0 wb01_2@0 wb01_3@0]

!Die latenten Mittelwerte werden frei geschätzt
[kwb_1 kwb_2 kwb_3];
output: stdyx;
Fehlermeldung:
THE STANDARD ERRORS OF THE MODEL PARAMETER ESTIMATES COULD NOT BE
COMPUTED. THE MODEL MAY NOT BE IDENTIFIED. CHECK YOUR MODEL.
vielen Lieben Dank im Voraus und liebe Grüße

[@QuantFish]

Liebe Frau Özsoy, ich vermute, dass Ihr Modell aufgrund der Fehlerkorrelationen unteridentifizeirt sein koennte. Daher bekommen Sie vermutlich diese Meldung. Mit nur 2 Indikatoren koennen Sie soweit ich mich erinnere nicht alle Fehlerkorrelationen frei schaetzen lassen. Ich favorisiere sowieso einen anderen (sparsameren) Ansatz mit einem Methodenfaktor fuer den 2. Indikator. Sie koennen das Video dazu hier ansehen:
ua-cam.com/video/5kv4poKf6Cw/v-deo.html
Auch sollten Sie pruefen, ob die Indikatoren jeweils zum selben Zeitpunkt hinreichend korreliert sind und ob die Faktoren ueber die Zeit hinweg substanziell korrelieren.
Ich hoffe, das hilft Ihnen weiter! Beste Gruesse, Christian Geiser