New Data Shows Much Improved Dropout Rate

by Bill Betzen

This past week the Dallas Independent School District released current enrollment numbers which indicate very positive progress in lowering the dropout rate. Using these enrollment numbers it was determined that the Cumulative Promotion Index has gone from 46.6% last year to 54.0% this year! This 7.4 percentage point gain is wonderful! Current enrollment numbers indicate it will continue to go up next year as well.

Other good news is that the improvements were spread all across Dallas, and were especially positive in North Dallas where the 6 high schools went from an average 9th to 12th grade promotion rate of 39.6% in 2008-2009 to 53.6% for 2009-2010! The graph below shows this years progress compared with the past 11 years. DISD well on the road to setting new records with the 2010 graduation rate.

Read the story at Bill's Blog

[Ed Note: Bill, I'm a little skeptical of this data. I'll clarify below...]

(Please pardon me, folks, while I geek out with Bill--and any other statisticians who want to get into the nitty gritty)

Bill, I'm going to exclude the latest year from the "CPI" on your statistics page ( and also assume that your figures are based on population means as opposed to sample means. So n=12, and you're roughly normally distributed (very slight negative skew -0.10084) around a mean of 44 with a standard deviation of 4.1888 (but let's go ahead and lose a degree of freedom and take s=4.3751) thus making your standard error 1.263. So a .95 ci of your sample data is 41.52 to 46.48 (sorry, everybody, I warned you this would get geeky!)

OK so far?

So let's bring your 54% figure back into the picture and assume the null hypothesis to be H0<=54, and alternate H1>54. A simple one sample Z-test statistic is -7.918 with a P-value of almost 1.

Obviously we don't have a sample size > 30 so central limit doesn't apply. Even so, it's highly unlikely you'd see this observation unless you had an obvious explanation for it (elimination of a high-dropout group, for example). What's more likely is that DISD changed it's statistical model.

Bottom line: statistically this is extremely unlikely and we'd be right coming to this conclusion 99.9999999% of the time.

I'd be very interested in the raw data--but I strongly suspect we'll be missing some key pieces needed to validate this claim.


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The numbers are never accurate.

How can you measure this? By the gross number of children attending at any given year and grade? There are many considerations including the influx of numbers after Katrina and the children forced into public school when the tuition funds for private education was vaporized last year for many families. These numbers are spun and there is no intention to have the true status of the education of Texan children known, to service a political agenda. Some candidate is taking credit for the improvements that are not really improvements, but the distortion of data and political spin. The numbers are not considerate of the fact that every child has rights by federal law for appropriate education to service their need to become educated, at the public expense. Our taxdollars are being spent in the DISD and there never is the correct accounting of the payroll, or attendence, or administation legal fees.
The only way to measure this is to really keep track from preschool through graduation. There needs to be a full and complete program (not waiting lists) to identify the needs of children from the pre school age, and the children need to have supports established before they are in school. Everytime a child is not attending it needs to be followed up on, and everytime any child starts in DISD, the numbers need to reflect the true and specific drop out as to identify that child as out of the system. The administration needs to have programs to work with the children, not at the children. The teachers do not have the freedom to do the job, per the direction of the administration. The children are not being serviced with the money provided for their education, and the board of trustees are not aware of the truth, and spin the lies and false data to mislead the voter.
The numbers are altered somewhere along the way, and that is the only thing we know for sure about the DISD!

The numbers are never accurate.

We owe it to our students to never rest the constant struggle for accuracy in the facts we use to help provide the best education/motivation possible for them. The simple "numbers are never accurate" attitude in no way helps them. Our nations struggle with math is sadly reflected in such an attitude. We must work harder for increasingly accurate numbers reflecting what is happening to our students. A multi-year enrollment by grade spreadsheet is a solid and auditable beginning. These numbers can be checked. That may be why the educational administration all over the US has tried to keep them hidden. They make it much harder, if not impossible, to create what they call "dropout rates" for Dallas ISD as well as Houston ISD that are allegedly below 2%. Both of these Texas school districts claimed such dropout rates within the past 8 years. The real 9th grade cohort dropout rate rarely if ever went below 50% in either of these cities. It was all a statistical/definition manipulation they pulled on the public.

We must have very solid numbers to work with.

Texas Dropout Rate - Responsibility?

mom of 2 quotes the TEA study online at
. While that report gives many very good ideas that are now part of the solution we see happening here in Dallas, the dropout numbers they quote are not accurate.

In the article it states: "The report notes that the cohort rate is the most accurate means of portraying the dropout problem because it is based on longitudinal data. For the class of 2008 cohort, Texas had a graduation rate of 79.1 percent."

That means that 79.1 percent of the 2004-2005 9th grade enrollment in Texas (383,447) should have received diplomas in 2008. 79.1% of 383,447 is 303,306 students who allegedly graduated. However, if you go to the TEA web site and look up the number of diplomas given out that year to the class of 2008 it is only 251,177. Some 52,000 students are missing in this tabulation and not counted as dropouts according to TEA. Sadly such misdirected counting in common from TEA. That is why Americas Promise and many other nationally respected advocates in the dropout prevention field quote numbers indicating that the graduation rate in Texas is about 64-67%.

Bottom line, who is responsible? We all are! We must pay attention to the numbers and try to determine if they are credible.

Who is responsible? Leigh Ann?
So who is responsible? Leigh Ann or the TEA?
THe only reason the DISD will care is to get more money.