|:: About PLSI ::
Inside This Section
The Paragon Learning Style
Inventory includes a 52-item adult version and a student learning style inventory
both of which can be self-scored and
obtain reliable measures of the 4 Jungian psychological/learning dimensions. The
Student version is
written for ages 8 and older. Each of the PLSI versions were last revised in
2003 and are being used
around the world by schools, businesses and individuals. For more about test
interpretation and theory
go to the interpretation page.
The 48-item version on
this site was revised in 1992. In 2003 another revision took place. Less
effective items were removed and more sound items were added so that latest
version has 52 items in total. Two advantages of 52 items are that first, it
reduces the number of ties and second, raises the reliability slightly. The item
functioning in the latest version has also been improved to produce higher
reliability, and factorial properties. While reliability is the primary concern
of many instruments of this type, as much attention was given to construct
validity when developing the PLSI. The factors or dimensions are not only very
independent, they reflect the proportions within the population. For example,
the PLSI will obtain about 50-50 thinkers and feelers, and judgers and
perceivers. This is not true of other instruments of this type.
Reliability and Validity
will provide information related to reliability and validity of the Paragon
Learning Style Inventory (PLSI) on the website. This summer we are planning
another round of testing, and will be able to report more precise reliability
figures at that point. But let us informally address some of the concerns
regarding the psychometric soundness of the PLSI.
- Any self-report
inventory is limited. That includes those like the MMPI that are developed by
factorial constructs rather than beginning with theoretical constructs. The
test-retest ability and the false positives of any inventory attempting
to make inferences regarding behavior or personality using a self-report
mechanism can never be perfect. The factors do not ever explain all of the
variance, and the subject will never be able to know him or herself
perfectly. So like the MBTI the PLSI gets at “true type” pretty well, but it
is not perfect.
- Data from the
Myers-Briggs suggests that 9 months later the retest stability of the MBTI is
about 60-70% (and about .90 for any single dimension, page 163; Manual for
Use). The PLSI has shown about the same level of stability. However, if a
person has a strong preference in any dimension the test-retest reliability
goes up to almost 1.00. An added benefit of the administration procedure for
the PLSI is that the participant can see their score immediately and determine
how close they are to the middle or either polar point. If the score is close,
the facilitator can help him/her understand that 2 things are important to do.
First, they need to look at additional material in the packet, especially the
pair-wise dimension lists to see if they can get further clarification to
their preference (the MBTI is not designed to do this). Second, they can see
that their preference is not that far to either side and will be able to
interpret their score and behavior with that in mind.
- Therefore, for a student
or adult to be able to use the PLSi data to understand him or herself, it is
important that they understand the dimensions enough to self-diagnose. This
understanding will mitigate much of the problems arising from offering
incorrect advice, or the participant making faulty assumptions.
- Our most current
analysis of the PLSI shows that the split half reliability of each of the
dimensions is between .90 and .94. We plan to do further analysis in the
coming year. Moreover, we use a series of analysis to determine the quality
of an items functioning.
- We have revised items
periodically in the past 10 years to improve their performance. A good item
has a high factor load (in a factor analysis) on the appropriate factor line.
All of our items function above +.40 and most in the +.60 and +.70 range. In
addition, all items are written to ensure that they obtain a correct
proportion of response of each type. Items that do not perform within 15% of
the mean are fixed or thrown out. For Example, you will see some changes
between the new 52-item version and the 48-item version online. There were 3
items that were outside the acceptable range.
- The primary analysis is
done by item. If an item functions, the scale will function, and if the scale
functions then the inventory does what it is intended to do. In essence, the
PLSi (or MBTI or Keirsey) is 4 separate inventories. The scales are almost
entirely independent (only the N/S and J/P scales have the slightest
- One psychometric
indication of theoretical validity is the evidence of a bi-modal distribution
for the PLSI. This result shows up in each analysis. A random characteristic
that exists naturally in the population (i.e., friendliness) exhibits a normal
(bell) distribution, with the highest frequency being exhibited at the mean.
If you examine the distribution PLSI scores, you will notice that the
distribution is very flat (i.e., those with a 10-3 score will be about as
common as those reporting a 7-6 score). And if the student were able to study
the dimension a bit more and gain a greater degree of self-awareness, the 9-4
score would become more common than the 7-6 score. The null hypothesis would
be that with 13 items, 3-4 students in 10 would score about in the middle on
any scale. But as you will see, the reality is that only about 1 in 20 will
not be able to break their tie on any scale (those student can be referred to
as X’s, and use interpretive material for both sides of that dimension).