*LOUISIANA BELIEVES - I VERIFY*
In his recent press release, superintendent John White
claimed that teachers are not leaving the classroom in greater numbers than
before, and he used flawed data to overstate the case that more
"ineffective" teachers than "highly effective" teachers
left. Here are his own numbers without
his bizarre spin:

"Ineffective" teachers are by definition

*(White's)*the lowest ranked 10% of the teaching force. 12% of teachers who left the classroom were "ineffective." "Highly Effective" teachers are the top 20%. According to White, 16% of teachers who left the classroom were "highly effective."
The other 72% of teachers leaving the classroom were
classified as "Effective." So
his own numbers show that 88% of teachers who left the classroom were effective
teachers.

White's conclusion?
"The teachers who are leaving are more likely to be
ineffective."

That statement is unjustified and an insult to my colleagues
-- all dedicated teachers -- who retired this year.

Furthermore, his data set is flawed; it lost track of
300-400 "highly effective" teachers over three years. White claims
that 19% of the teachers who stayed and 16% who left were "highly
effective." This is mathematically impossible
since LDOE set a quota of 20% for "highly effective" teachers.

Based on the LDOE data and its quota, there were 7725
"highly effective" teachers. Using White's figures and accounting for
the maximum possible rounding error, a (maximum) total of 7419 "highly
effective" teachers either left the classroom or stayed.

What happened to the missing 306 "highly
effective" teachers? They were lost in data error.

They probably were mis-categorized. This kind of error could affect the careers
of the very teachers the new evaluation system is supposed to identify and
reward. Furthermore, this skews the
data; the percentage of "highly
effective" teachers that left is likely 2% higher than White stated. This
weakens the his assertion even further.

This data was likely hurriedly compiled because LDOE
recently redefined "highly effective." (Teachers have become frustrated with the
continual changes to the new evaluation system which was implemented incomplete
and untested.) In his haste to create
spin, John White sacrificed the truth of accuracy in order to muddy the waters.

How many teachers have left this year? White's data sample shows that 1204 left last
school year and that 1157 have already left this year, which is barely half
over.

When the number doubles to over 2000 by the school year's
end, I will call that a mass exodus.

Is it a wonder why?

Herb Bassett, Grayson, LA

*Further Explanation and Documentation*
In his LDOE website press release, White tortured some data
to overstate the case that more "ineffective" teachers than
"highly effective" teachers left.
Here are his own numbers in table form without his bizarre presentation:

__Classification Percent of Teachers Percent of Teachers who left (Overall)__

Ineffective 10 12

Effective: Emerging 40 42

Effective: Proficient 30 30

Highly Effective 20 16

These numbers fail to justify White's insult to the dignity
of the 88% of teachers leaving the profession who

__were__effective.
* * * * *

White claims that 19% of the teachers who stayed were
"highly effective;" only 16% of the teachers who left were
"highly effective." This is
mathematically impossible since LDOE set a quota of 20% for "highly
effective" teachers.

Let's account for all those "highly effective"
teachers using his (three-year) "Overall" data (the year by year data
works out similarly).

*To be completely accurate in disclosure, since this is three-year data, the figure 34890 teachers who stayed is technically 34890 teacher-years. Many teachers in the 34890 figure are counted three times for the three different years in the data. Still its use in the computation is correct and appropriate. It is the same method used by LDOE in White's interpretation of the data.*
3734 teachers left, of which 16% were highly effective. .16499 is the highest number that rounds to
16%; we will use it to compute the number of "highly effective"
teachers who left (results rounded to the nearest whole teacher).

3734 x .16499 = 616

34890 teachers stayed, 19% were "highly
effective." Again we use the highest number that rounds to 19%.

34890 x .19499 = 6803

We have accounted for a maximum of 616 + 6803 = 7419
"highly effective" teachers.

There were 3734 + 34890 = 38624 teachers total in the
data. By LDOE's definition, exactly
20.0% of those were "highly effective."

38624 x .20 = 7725

Over the three years, there were 7725 "highly
qualified" teachers of which a 7419 either left or stayed.

What happened to the other 306? They were lost in data error
by LDOE.

* * * * *

How do we establish the assertion that the percent of
"highly effective" teachers leaving the classroom was likely 2%
higher than the 16%?

Repeating the calculations above with .16000 and .19000
instead of the higher figures, we find that instead of 306 (with is the minimum
possible number of teachers lost in the data), 498 are lost in the data. This figure would be in the middle instead of
the minimum or maximum.

Using the figure of 12% of teachers leaving the workforce,
we compute the increased number of "highly effective teachers leaving.

498 x .12 = 59.76

Now 59.76 is 1.6% of the total number of teachers leaving.

59.76 / 3724 =
.016004 or 1.6004%

That rounds to 2%, and therefore is likely to increase the
16% to 18%.

Since LDOE made that miscategorization error, that 2% had to
come from one of the other categories, most likely from Effective: Proficient,
so his data table probably should have read:

__Classification Percent of Teachers Percent of Teachers who left (Overall)__

Ineffective 10 12

Effective: Emerging 40 42

Effective: Proficient 30 28

Highly Effective 20 18

White's assertion that a higher proportion of
"ineffective" teachers left than the proportion of "highly
effective" teachers is supported by the data to some degree. However, common sense says that poeple who
struggle at something are going to seek something else to do, and those who are
good at what they do are likely to be comfortable and continue doing it.

*While this might show up in large group data, I do not concede that VAM is an accurate tool for measuring individual teachers.*His assertion that "The teachers who are leaving are more likely to be ineffective" is misleading because when other categories of "effective" teachers are considered, it is very weakly supported in that context.
* * * * *

Finally, the LDOE data states that 8% of of teachers staying
and 12% of teachers leaving are "ineffective". My mental arithmetic says this is not within
rounding error of the 10% quota for that category, but I have not explored that
problem with the data.

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