alignByLoadings: Align constructs by loadings on first pricipal component.

Description Usage Arguments Details Value Note Author(s) References See Also Examples

View source: R/calc.r

Description

In case a construct loads negatively on the first principal component, the function alignByLoadings will reverse it so that all constructs have positive loadings on the first principal component (see deatil section for more).

Usage

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alignByLoadings(x, trim = 20, index = TRUE)

Arguments

x

repgrid object.

trim

The number of characters a construct is trimmed to (default is 10). If NA no trimming is done. Trimming simply saves space when displaying the output.

index

Whether to print the number of the construct (e.g. for correltion matrices). The default is TRUE.

Details

The direction of the constructs in a grid is arbitrary and a reflection of a scale does not affect the information contained in the grid. Nonetheless, the direction of a scale has an effect on inter-element correlations (Mackay, 1992) and on the spatial representation and clustering of the grid (Bell, 2010). Hence, it is desirable to follow a protocol to align constructs that will render unique results. A common approach is to align constructs by pole preference, but this information is not always accessible. Bell (2010) proposed another solution for the problem of construct alignment. As a unique protocol he suggests to align constructs in a way so they all have positive loadings on the first component of a grid PCA.

Value

An object of class alignByLoadings containing a list of calculations with the following entries:

cor.before

Construct correlation matrix before reversal

loadings.before

Loadings on PCs before reversal

reversed

Constructs that have been reversed

cor.after

Construct correlation matrix after reversal

loadings.after

Loadings on PCs after reversal

Note

Bell (2010) proposed a solution for the problem of construct alignment. As construct reversal has an effect on element correlation and thus on any measure that based on element correlation (Mackay, 1992), it is desireable to have a standard method for construct alignment independently from its semantics (preferred pole etc.). Bell (2010) proposes to align constructs in a way so they all have positive loadings on the first component of a grid PCA.

Author(s)

Mark Heckmann

References

Bell, R. C. (2010). A note on aligning constructs. Personal Construct Theory & Practice, 7, 42-48.

Mackay, N. (1992). Identification, Reflection, and Correlation: Problems in ihe bases of repertory grid measures. International Journal of Personal Construct Psychology, 5(1), 57-75.

See Also

alignByIdeal

Examples

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  # reproduction of the example in the Bell (2010)
  # constructs aligned by loadings on PC 1
  bell2010                    
  alignByLoadings(bell2010)   

  # save results
  a <- alignByLoadings(bell2010)
  
  # modify printing of resukts
  print(a, digits=5)
  
  # access results for further processing  
  names(a)
  a$cor.before
  a$loadings.before
  a$reversed
  a$cor.after
  a$loadings.after

markheckmann/OpenRepGrid documentation built on April 30, 2021, 2:33 a.m.