School-Performance
Dashboard
Note: This excerpt is my contribution to a
longer presentation. Please click through it
in presentation view to see my step-bystep animations. –Sean
Priscilla (Penny) Wohlstetter, Ph.D.
Archana Patel
Sean Parker
Cowen Institute
Tulane University
Layers of Information
Dashboard For Example School
Layers of Information
Dashboard For Example School
marks the top 20%.
marks the bottom 20%.
Layer Ia: Note the colors.
Layer Ib: Note the numbers.
The numbers are percentile ranks. A percentile rank of 83 means
that this school is performing better than approximately 83% of
schools in the sample.
Is 83 good? It’s all relative.
The fastest glacier is still slow.
The slowest shooting star is still fast!
Layers of Information
Dashboard For Example School
Digging Deeper
What is the school’s actual SPS Score?
This school is at the top of the pack in SPS,
but what does the pack look like?
Layers of Information
Dashboard For Example School
This school has an
SPS Score of 67.
The bulk
of
schools
fall in
this
range.
56 and 67 mark the
bottom 20% and the
top 20%,
respectively.
Layers of Information
Dashboard For Example School
Digging Deeper
What does the 75 for Academic Environment mean? On the
face, it means that this school scored higher than about 75%
of the schools in the sample. But, there is more to uncover.
This school has an
SPS Score of 67.
56 and 67 mark the
bottom 20% and the
Relatively
Low
top 20%,
respectively.
Layer IIa: Note the indicators for the domain.
Layer IIb: Note the school’s actual values.
Layer IIc: Note the placing in each pack.
Layer IId (subtle): Note the weighting. (See Appendix)
Layers of Information
Dashboard For Example School
Digging Deeper
What is statistical control? What is the difference between Per Pupil Expenditure Controlling
for Number of Students and Per Pupil Expenditure (Uncontrolled)? What is the difference
between Student-Faculty Ratio and Controlled Student-Faculty Ratio?
It is one thing to have a Student-Faculty Ratio of 20 when you have 200 students. It is another
thing to have a Student-Faculty Ratio of 20 when you have 800 students.
When we statistically control for number of students, we ask of each school, what is your
Student-Faculty Ratio over and above (or under and below) what we would predict based your
number of students?
Layers of Information
Dashboard For Example School
This school has a Student-Faculty
Ratio of 11, which puts it in the
middle of the pack.
But, the pack is comprised of schools
of various sizes. Let’s simultaneously
consider Student-Faculty Ratio and
Number of Students.
Notice the three schools with about
600 students each.
One has an S-F Ratio of about 25,
another of about 14, and another of
about 8.
.
Based on a fitted trend line, we
predict an S-F Ratio of about 15 for
schools with 600 students.
.
..... ..
We see that one school has an S-F
Ratio 10 units greater than .we would
.
predict based on Number of Students.
Another school is 1 unit less than our
prediction, and another school is 7
units less than our prediction.
.
Layers of Information
Dashboard For Example School
Our school has a StudentFaculty Ratio of 11.
It has a school size of about
180.
Based on a school size of
about 180 students, we would
predict a Student-Faculty
Ratio of about 6.
Now, we can put it all together…
Thus, the Student-Faculty
Ratio of 11 is 5 units above
what we would predict based
on number of students. That
5 units is the Controlled
Student-Faculty Ratio.
Statistical control is the 3rd
(and most complicated) layer
of information.
A Comprehensive View of Performance
Dashboard For Example School
Appendix: Weighting
Digging Deeper
Layer IId (subtle): Note the weighting.
The percentile rank for the domain is based on a weighted
average of the indicators. First, we give the indicators
equal weight, as we standardize their various scales to a
mean of zero and a standard deviation of one, roughly
translating each indicator to a scale from -3 to 3. Then, we
give each indicator a deliberate weight (decided by the
consortium with a statistician’s guidance), and this
deliberate weight is denoted by the dots under the value.
Thus, we see that the SPS Score is weighted most and that
the PPE (Uncontrolled) is weighted least.
4
Dots
3
Dots
3
Dots
2
Dots