Computes the Fornell-Larcker matrix.

```
calculateFLCriterion(
.object = NULL,
.only_common_factors = TRUE,
...
)
```

## Arguments

- .object
An R object of class cSEMResults resulting from a call to `csem()`

.

- .only_common_factors
Logical. Should only concepts modeled as common
factors be included when calculating one of the following quality critera:
AVE, the Fornell-Larcker criterion, HTMT, and all reliability estimates.
Defaults to `TRUE`

.

- ...
Ignored.

## Value

A matrix with the squared construct correlations on the off-diagonal and
the AVE's on the main diagonal.

## Details

The Fornell-Larcker criterion (FL criterion) is a rule suggested by Fornell and Larcker (1981)
to assess discriminant validity. The Fornell-Larcker
criterion is a decision rule based on a comparison between the squared
construct correlations and the average variance extracted (AVE).

The FL criterion is inherently tied to the common factor model. It is therefore
unclear how to meaningfully interpret the FL criterion in the context of a
model that contains constructs modeled as composites.

## References

Fornell C, Larcker DF (1981).
“Evaluating structural equation models with unobservable variables and measurement error.”
*Journal of Marketing Research*, **XVIII**, 39--50.