What Is a Second Order Confirmatory Factor Analysis Model in SEM?

A second order CFA is a “higher order” construct that is measured by latent constructs. For instance, let’s say we want to model a construct called “Unique Experience”. This construct is the degree to which customers think their experience was unique or different compared to a normal experience. This second order construct of “Unique

Reflective vs. Formative Indicators of SEM Model

Based on classical test theory (Lord and Novick 1968), when an unobservable variable causes changes in its indicators, the specification of these indicators is reflective (For- nell and Bookstein 1982) or effect indicators (Bollen and Lennox 1991). By far, this is the most common type of measurement model in which the direction of influence

Potential Identification Problems With Formative Indicators in SEM Model

A formative construct will have identification problems in SEM if additional steps are not taken. The first way to rectify the identification problem is to include two reflective indica- tors from the formative unobservable construct. These two reflective indicators should try to capture the overall theme of the formative construct.You need to know if

Dependent Relationships With Formative Constructs in SEM Model

As stated earlier, a formative construct is defined by its indicators. A change in a formative unobserved construct cannot take place without a change also taking place in the indicators. Hence, I think it is a good idea to discuss the appropriate way to model relationships in a SEM model with formative constructs. If

Higher Order Formative Construct Example of SEM Model

Let’s look at an example of a higher order (second order) construct that has formative indi- cators in AMOS. Using our example from earlier in the chapter, the higher order construct of Unique Experience is formed by two first order constructs of Surprise and Empathy.We have also included two reflective indicators off the higher

How Do I Present the Result of My Higher Order Formative SEM Model?

The results of the CFA for the first order dimensions should be presented in a dedicated CFA table. For the first order constructs’ relationship to the higher order construct, I prefer to put this information in a structural relationship table. I also like to include the actual wording of the identification items to give

Error Messages in AMOS

If you encounter an error message in AMOS while testing your measurement model, here are some of the most common causes I have found along with potential remedies. The model is unidentified—after running the analysis, this error message will appear in the “Notes for Model” link of the output. Figure 4.52 Error Message for

Path Analysis in SEM Model

So far, we have talked only about the measurement model; now let’s talk about the struc- tural model.The structural model’s focus is on examining the relationships between constructs. Hence, we will look at how independent constructs influence dependent constructs or, in more complex models, how dependent variables influence other dependent variables. The first type

Can I Use a Correlation Matrix as My Data Input?

Yes, AMOS allows you to use a correlation matrix as data input, but you need to include the standard deviation, mean, and sample size for each construct. Typically, you will see path models used when the data input is a correlation matrix instead of the raw data. For many correlation analyses, the researcher is

Full Structural Model Analysis

A full structural model assesses the relationships between constructs but also includes the measurement indicators for each variable. A full structural model will allow you to account for the measurement error in a construct’s indicators while also assessing the relationships between constructs.You will initially draw all the constructs and indicators like you did in

How Do I Report My Full Structural Model Results?

With the structural model, it is a good idea to present standardized regression weights, t-values, model fit statistics, and R2 values. I like to present R2 values of the dependent con- structs so the reader can see how much of the variance is being explained with my independ- ent variables. I also like to

Using Specification Search to Aid in Model Trimming and Fit in Full Structural Models

After you have conceptualized your model, you can use the specification search function to aid in trimming/fitting of your model.Trimming a model means removing some paths that might not be contributing much to the overall model.The specification search function will propose numerous different proposed models to see which one has the best model fit.This

What Are Alternative Models of Full Structural Models, and Why Should I Be Concerned With Them?

In the past, a heavy emphasis was placed on the idea of alternative models, or the abil- ity to show the superiority of your research model compared to other potential rival models. While still a valid procedure, the popularity of requiring alternative models in research has waned. The main reason is that researchers would

How Do I Add a Control Variable to My Structural Model?

At times, you might want to control for other potential influences in your model. Common control variables are demographics of a sample (gender, age, income) but can also be attitudinal or psychographic measures.With a control variable, you are accounting for the potential influ- ence of these variables in order to get unbiased estimates.To put

Two Group Analysis in Full Structural Models

A two group analysis can see if differences exist in the relationships proposed in a model across groups. Performing a two group analysis is very similar to the discussion about measurement invariance in Chapter 4. Let’s continue with the example used in the full structural analysis of Adaptive Behavior and Servicescape leading to Customer

What if I Have More Than Two Groups in My Full Structural Model Analysis?

Let’s say you have three groups in your analysis and want to see if the groups are significantly different from one another. AMOS will let you set up a third group in the models window and will run the analysis across all three groups. The problem is that AMOS examines these potential differences as

When I Try to Run My Structural Analysis, I Get an Error Message About My Matrix Not Being Positive Definite

You will get this message when you have a negative eigenvalue in your matrix. A non-positive matrix is often the result of multicollinearity. For instance, let’s say you are examining the eating habits of children and you have two variables of “child height” and “child weight”. The linear correlation between these two constructs might

Can I Correlate the Error Terms of Two Unobservable Constructs in a Full Structural Model?

The majority of the time, correlating error terms of unobservable constructs is not permis- sible, but there are some exceptions. If two constructs are systematically correlated with one another but not causally correlated, then you can correlate the error terms. This would be where two constructs are highly correlated with one another but not

How Do I Present the Results of My Two Group Analysis in Full Structural Models?

Here is a way you can present your results in a table format that will be easy for the reader to understand. In a two group analysis, you need to present the relationship strength (standard- ized coefficient) and t-values for each relationship.You also need to show the significance of the comparison across groups.This can

How Do I Search for Multivariate Outliers in Full Structural Models?

If your model fit is poor and the modification indices are providing no help, you might want to examine the multivariate outliers in your data set. A multivariate outlier is a collection of unusual or “out-of-the-norm” scores across multiple variables. Let’s go back to the full structural model example. If you go into the