Various graphs for deaths from COVID-19, so far

I wrote that I would show you what various graphs of various types of simple models look like for deaths so far due to the current corona virus: linear, exponential, polynomial, and so on. I think that a fourth-degree (not third-degree, like I wrote earlier) seems to fit the data best so far, and that’s better than exponential growth.

First, let’s look at a straight-line best-fit model, superimposed by Excel on the data. (Note: deaths are on the Y, or vertical, axis; the X-axis represents days since the beginning of March. So today, the 6th of April, is day 37 (31 + 6). The dotted red line represents the line of best fit, and the blue dots are the CDC-announced numbers of deaths so far.

is it linear

As you can see, the straight dotted line doesn’t fit the data very well at all. R-squared, known as the correlation coefficient, tells us numerically how well it fits. If R or R^2 equals 1.000, then you have absolutely perfect correlation of the data to your model. Which we do NOT have here. By the way, in that model, then by mid-June we would have about 22,000 dead from this disease.

OK, let’s look at an exponential curve-of-best fit next:

is it exponential

As you can see, this red curve fits the data a LOT better, and R-squared is a lot higher.

Unfortunately.

We do NOT WANT EXPONENTIAL GROWTH OF THIS OR ANY OTHER DISEASE, BECAUSE IT MEANS WE ALL GET IT! In fact, if this model is accurate and isn’t slowed down, then by mid-June, just plugging in the numbers, we would have 3.3 BILLION (not million) people dead in the US alone. Fortunately, that won’t happen.

BUT there are some parts of the data where the curve doesn’t fit perfectly — let me point them out:

is it exponential -2

At the upper right-hand end, the red dotted line is quite a bit higher than the blue dots. Fortunately. And near the middle of the graph, the blue dots of death are higher than the red line.

OK, let’s look at some polynomial models instead:

is it a second degree polynomial

This is a fancy version of the simple y=x^2 parabolas you may have graphed in Algebra 1. Once again, this doesn’t do a terrific job of conforming to the actual data. At the right-hand end, the blue dots of death are higher than the curve. In addition, if we continued the red curve to the left, we would find that something like two thousand people had already died in the US, and presumably came back to life. Which is ridiculous.

However, if this model were to hold true until mid-June, we would have 127 thousand dead. Not good.

Let’s try a third-degree polynomial (a cubic):

is it a third degree polynomial

That’s pretty remarkable agreement between the data and the equation! That’s the equation I was using in my earlier post. The R-squared correlation is amazing. Unfortunately, if this continues to hold, then we would have about 468 thousand dead in the US.

Let’s continue by looking at a fourth-degree polynomial curve fitted to the data:

is it a fourth degree polynomial

That is an amazingly good fit to the data! Unfortunately, let’s hope that it won’t continue to fit the data, because if it does, then we are looking at a little over a MILLION dead.

Let’s hope we can get these totals to level off by physically distancing ourselves from other households, washing our hands, and getting proper protective garments and testing technology to our medical personnel.

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Here’s another model that unfortunately does NOT work: logarithmic growth. If it were the case, then we would have about 10,700 deaths by mid-June.

is it logarithmic

 

People are Not Cattle!

This apparently did not occur to William Sanders.

He thought that statistical methods that are useful with farm animals could also be used to measure effectiveness of teachers.

I grew up on a farm, and as both a kid and a young man I had considerable experience handling cows, chickens, and sheep. (These are generic critter photos, not the actual animals we had.)

I also taught math and some science to kids like the ones shown below for over 30 years.

guy teaching  deal students

Caring for farm animals and teaching young people are not the same thing.

(Duh.)

As the saying goes: “Teaching isn’t rocket science. It’s much harder.”

I am quite sure that with careful measurements of different types of feed, medications, pasturage, and bedding, it is quite possible to figure out which mix of those elements might help or hinder the production of milk and cream from dairy cows. That’s because dairy or meat cattle (or chickens, or sheep, or pigs) are pretty simple creatures: all a farmer wants is for them to produce lots of high-quality milk, meat, wool, or eggs for the least cost to the farmer, and without getting in trouble.

William Sanders was well-known for his statistical work with dairy cows. His step into hubris and nuttiness was to translate this sort of mathematics to little humans. From Wikipedia:

“The model has prompted numerous federal lawsuits charging that the evaluation system, which is now tied to teacher pay and tenure in Tennessee, doesn’t take into account student-level variables such as growing up in poverty. In 2014, the American Statistical Association called its validity into question, and other critics have said TVAAS should not be the sole tool used to judge teachers.”

But there are several problems with this.

  • We  don’t have an easily-defined and nationally-agreed upon goal for education that we can actually measure. If you don’t believe this, try asking a random set of people what they think should be primary the goal of education, and listen to all the different ideas!
  • It’s certainly not just ‘higher test scores’ — the math whizzes who brought us “collateralization of debt-swap obligations in leveraged financings” surely had exceedingly high math test scores, but I submit that their character education (as in, ‘not defrauding the public’) was lacking. In their selfishness and hubris, they have succeeded in nearly bankrupting the world economy while buying themselves multiple mansions and yachts, yet causing misery to billions living in slums around the world and millions here in the US who lost their homes and are now sleeping in their cars.
  • Is our goal also to ‘educate’ our future generations for the lowest cost? Given the prices for the best private schools and private tutors, it is clear that the wealthy believe that THEIR children should be afforded excellent educations that include very small classes, sports, drama, music, free play and exploration, foreign languages, writing, literature, a deep understanding and competency in mathematics & all of the sciences, as well as a solid grounding in the social sciences (including history, civics, and character education). Those parents realize that a good education is expensive, so they ‘throw money at the problem’. Unfortunately, the wealthy don’t want to do the same for the children of the poor.
  • Reducing the goals of education to just a student’s scores on secretive tests in just two subjects, and claiming that it’s possible to tease out the effectiveness of ANY teacher, even those who teach neither English/Language Arts or Math, is madness.
  • Why? Study after study (not by Sanders, of course) has shown that the actual influence of any given teacher on a student is only from 1% of 14% of test scores. By far the greatest influence is from the student’s own family background, not the ability of a single teacher to raise test scores in April. (An effect which I have shown is chimerical — the effect one year is mostly likely completely different the next year!)
  • By comparison, a cow’s life is pretty simple. They eat whatever they are given (be that straw, shredded newspaper, cotton seeds, chicken poop mixed with sawdust, or even the dregs from squeezing out orange juice [no, I’m not making that up.]. Cows also poop, drink, pee, chew their cud, and sometimes they try to bully each other. If it’s a dairy cow, it gets milked twice a day, every day, at set times. If it’s a steer, he/it mostly sits around and eats (and poops and pees) until it’s time to send  them off to the slaughterhouse. That’s pretty much it.
  • Gary Rubinstein and I have dissected the value-added scores for New York City public school teachers that were computed and released by the New York Times. We both found that for any given teacher who taught the same subject matter and grade level in the very same school over the period of the NYT data, there was almost NO CORRELATION between their scores for one year to the next.
  • We also showed that teachers who were given scores in both math and reading (say, elementary teachers), there was almost no correlation between their scores in math and in reading.
  • Furthermore, with teachers who were given scores in a single subject (say, math) but at different grade levels (say, 6th and 7th grade math), you guessed it: extremely low correlation.
  • In other words, it seemed to act like a very, very expensive and complicated random-number generator.
  • People have much, much more complicated inputs, and much more complicated outputs. Someone should have written on William Sanders’ tombstone the phrase “People are not cattle.”

Interesting fact: Jason Kamras was considered to be the architect of Value-Added measurement for teachers in Washington, DC, implemented under the notorious and now-disgraced Michelle Rhee. However, when he left DC to become head of Richmond VA public schools, he did not bring it with him.

 

A geometry lesson inspired by a silvering company – and a rant about computerized learning programs

Here is some information that teachers at quite a few different levels could use* for a really interesting geometry lesson involving reflections involving two or more mirrors, placed at various angles!

Certain specific angles have very special effects, including 90, 72, 60, 45 degrees … But WHY?

This could be done with actual mirrors and a protractor, or with geometry software like Geometer’s Sketchpad or Desmos. Students could also end up making their own kaleidoscopes – either with little bits of colored plastic at the end or else with some sort of a wide-angle lens. (You can find many easy directions online for doing just that; some kits are a lot more optically perfect than others, but I don’t think I’ve even seen a kaleidoscope that had its mirrors set at any angle other than 60 degrees!)

I am reproducing a couple of the images and text that Angel Gilding provides on their website (which they set up to sell silvering kits (about which I’ve posted before, and which I am going to attempt using pretty soon, on a large astronomical mirror I’ve been polishing for quite some time)).

At 72º you see 4 complete reflections.

When two mirrors are parallel to each other, the number of reflections is infinite. Placing one mirror at a slight angle causes the reflections to curve.

 

https://angelgilding.com/multiple-reflections/

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Rant, in the form of a long footnote:

* assuming that the teacher are still allowed to initiate and carry out interesting projects for their students to use, and aren’t forced to follow a scripted curriculum. It would be a lot better use of computers than forcing kids to painfully walk through (and cheat, and goof off a lot) when an entire class is forced to use one of those very expensive but basically worthless highly-centralized, district-purchased computer-managed-instruction apps. God, what a waste of time – from personal experience attempting to be a volunteer community math tutor at such a school, and also from my experience as a paid or volunteer tutor in helping many many students who have had to use such programs as homework. Also when I was required to use them in my own classes, over a decade ago, I and most of my colleagues found them a waste of time. (Not all – I got officially reprimanded for telling my department chair that ‘Renaissance Math’ was either a ‘pile of crap’ or a ‘pile of shit’ to my then-department head, in the hearing of one of the APs, on a teacher-only day.

Keep in mind: I’m no Luddite! I realized early on that in math, science, and art, computers would be very, very useful. I learned how to write programs in BASIC on one of the very first time-share networks, 45 years ago. For the first ten years that my school system there was almost no decent useful software for math teachers to use with their classes unless you had AppleII computers. We had Commodore-64’s which were totally incompatible and there were very few companies (Sunburst was one) putting out any decent software for the latter. So when I saw some great ideas that would be ideal for kids to use on computers to make thinking about numbers, graphs, and equations actually fun and mentally engaging, often I would have to write them my self during whatever free time I could catch, at nights and weekends. Of course, doing this while being a daddy to 2 kids, and still trying to teach JHS math to a full load of students (100 to 150 different kids a day at Francis Junior High School) and running a school math club and later coaching soccer. (I won’t say I was a perfect person or a perfect teacher. I believe I learned to give better math explanations than most, didn’t believe that you either have a ‘m,ath gene’ or you don’t, at times had some interesting projects, and at times was very patient and clear, but had a terrible temper and often not good at defusing things. Ask my kids or my former students!) Later on, I collaborated with some French math teachers and a computer programmer to try to make an app/program called Geometrix for American geometry classes that was supposed to help kids figure out how to make all sorts of geometric constructions and then develop a proof of some property of that situation. It was a failure. I was the one writing the American version, including constructions and tasks from the text I was currently using. There was no way I could anticipate what sorts of obstacles students would find when using this program, until I had actual guinea pig students to use them with. Turns out the final crunch of writing however many hundreds of exercises took place over the summer, and no students to try them on. Figuring out hints and clues would require watching a whole bunch of kids and seeing what they were getting right or wrong. In other words, a lot of people’s full time job for a long time, maybe paying the kids as well to try it out so as to get good feedback, and so on. Maybe it could work, but it would require a lot more investment of resources that the tiny French and American companies involved could afford. We would have really needed a team of people, not just me and a single checker.

I find that none of these computer-dominated online learning programs (much less the one I worked on) can take the place of a good teacher. Being in class, listening to and communicating logically or emotionally with a number of other students and a knowledgeable adult or two, is in itself an extremely important skill  to learn. It’s also the best way to absorb new material in a way that will make sense and be added to one’s store of knowledge. That sort of group interaction is simply IMPOSSIBLE in a class where everybody is completely atomized and is on their own electronic device, engaged or not.

Without a human being trying to make sense out of the material, what I found quite consistently, in all the computerized settings, that most students absorbed nothing at all or else the wrong lessons altogether (such as, ‘if you randomly try all the multiple choice answers, you’ll eventually pick the right one and you can move on to some other stupid screen’; it doesn’t matter that all your prior choices were wrong; sometimes you get lucky and pick the right one first or second! Whee! It’s like a slot machine at a casino!).

By contrast, I found that with programs/apps/languages like Logo, Darts, Green Globs, or Geometer’s Sketchpad, with teacher guidance, students actually got engaged in the process, had fun, and learned something.

I find the canned computer “explanations” are almost always ignored by the students, and are sometimes flat-out wrong. Other times, although they may be mathematically correct, they assume either way too much or way too little, or else are just plain confusing. I have yet to detect much of any learning going on because of those programs.

 

DC Women’s March – 2020 (Today!)

I am glad that my wife and I took part in today’s march. It was inspiring to us to talk with so many fine young folks (some men, too) along the march route; some of them told us that we veteran activists from the 60’s, 70’s and 80’s inspired them, which was nice to hear. It was fun swapped some ideas and stories with new folks and veterans of, say, marches and demonstrations in Los Angeles and the Bay Area of California…

Some of the signs were brilliant!

IMG_6055

IMG_6081

IMG_6112

It was quite cold, and sometimes sleeting and raining; my wife and I both found our cell phone batteries dying because of the low temperatures, so I don’t have nearly as many photos as I would have liked. Fortunately w both had dressed properly – long acrylic thermal underwear, woolen sweater and socks, monk’s hood, parka hood, and umbrella for me; my wife looked a bit like an Inuit.

IMG_5996      IMG_5980

A couple of comments:

  • It didn’t look like organizers had really agreed on a common platform for chants, songs, or whatever. I persuaded someone with a bullhorn to lead a chant concerning immigration (see my last post).
  • We probably represented hundreds, if not thousands, of different organizations, but most of us only had the most tenuous links to said organizations — we had signed something online somewhere, or donated something, or maybe been to a meeting or two.
  • Definitely mostly white and middle-class, though latinxes, african-americans, and asians were definitely represented.
  • It was great that mostly young women had organized this, and I was just along an ally.
  • I didn’t hear people talking about the impeachment process, probably because we all know that there is between zip and nada percent chance that the Senate will actually convict and remove lying sack of shit #45 from office.
  • We need to acknowledge that the attacks by Arne Duncan and the Obama Administration on teachers during the 8 years they were in office — despite all their flowery, progressive rhetoric — were worse even than what Trump and Betsy Devos have been capable of doing, and were also worse than what we suffered under GWBush 2. That’s saying a lot. I think the demoralization of teachers definitely led to the election of Mango Mussolini, because so many Democratic party activists all across the country were teachers. In fact, during those 8 years, the local precinct, county, and state Democratic organizations were shredded to pieces or collapsed. The Tea Party and future Trumpsters were extremely energized and got their people out to vote at every election, and caused thousands of seats to turn Fascist Red.
  • We need to be much, much better organized. The Nazi Party in Germany before 1932 (Ie before Hitler was appointed Chancellor)had uniformed, armed, militias (Brownshirts and Blackshirts) that were equipped, trained, and funded by the German (especially Prussian) military General Staff. We don’t have that here, yet, in the USA, but we do know that neo-Nazis, Kluxers, and the like do send their young aficionados to enlist in the military, to get weapons training, and to try to incite and recruit other violent racists. Knowing that the racists are in fact emboldened, and have been in fact arming themselves and organizing, we need to be better organized and to take them seriously. When Trump and his acolytes are [I hope] thrown out in a landslide on November 3, the neo-Nazis he has emboldened may cause serious trouble. We can’t predict the future.
  • All the people I talked to agreed with me that Alexandria Ocasio-Cortez is one of the smartest politicians we had ever seen, and the most inspiring and honest. We were uniformly in awe of her ability to run a House hearing and to skewer the bad guys with their own words and with facts. I hope nothing bad happens to her and that she can run for higher office and help organize a good, progressive movement.
  • I have no faith in any organization that I am aware of. I furthermore am going to state that what the Soviet Union did to its own citizens under Stalin’s watch (in particular) was absolutely inexcusable, betraying just about every single humanitarian principle that socialists, progressives, anarchists, or communists of any stripe have fought for — except for the principle of killing (mostly) imagined enemies of the people, working class, or proletariat. Think about it: though we will never know the final toll, I estimate that on the average several hundreds of people were executed or died of mistreatment or starvation every single day in the USSR during the roughly 30-year period 1923-1953. Long story.
  • IMG_6111

    My estimate of the crowd at this march is probably pretty low, since I could never see the entire march at once and don’t own a helicopter. Neither am I privy to overhead photos of the event. However, when I was at the south end of the Ellipse, I stood up on a park bench and could see a lot of it; perhaps the panorama picture I took, above, will make some sense. (As I said, my phone did NOT like the cold; in the future I’m going to need to take chemical hand-warmers to put around it)

  • That location was a fine one for giving Mr Maralago a single=fingered salute. A number of people joined me.
  • It seemed to me that in every seven-foot (or 2-meter) longitudinal section of the march, there were somewhere between 20 and 60 people (so 3 to 9 people per longitudinal foot) – we filled the streets including the sidewalks as well. (My wife and I bailed out at the intersection of 16th and H, at the north side of Lafayette Park and went to warm up with a delicious late brunch at Fiola da Mare, which was quite a nice little luxury we’d never experienced.)
  • At one point, I could see people still marching on Constitution Avenue all the way to the corner of 15th and Constitution, on the latter heading west, and then all the way up 17th street up to Lafayette Square. How many marchers there were further towards either the head or tail of the march, I could not see. It was definitely smaller than a couple of the other women’s marches I attended, if I remember correctly.
  • Using the scale on the map I’m showing you below,  I think that I myself could see about 4,000 feet worth of people marching, which would mean somewhere between 11,000 to 35,000 people. There were clearly many more, but how many, I have no idea. (I’m making this estimate because Park Service no longer provides estimates.)

women's march 2020

Anybody have a better estimate? As I said, I’m sure mine is low. The comment button below is really hard to find.

PISA shows great US education progress under Common Core, charter proliferation, reforms. (JUST KIDDING!)

If there is anything that the recent PISA results show, it’s that the promises by David Coleman, Bill Gates, Michelle Rhee, Betsy Devos, Arne Duncan, Barack Obama, and others of tremendous achievement increases and closing socioeconomic gaps with their ‘reforms’ were completely unfilled. I am copying and pasting here how American students have done on the PISA, a test given in many, many countries, since 2006. There have been tiny changes over the past dozen years in the scores of American students in reading, math, and science, but virtually none have been statistically significant, according to the statisticians who compiled and published the data.

Then again, nearly any classroom teacher you talked to over the past decade or two of educational ‘reforms’ in American classrooms could have told you why and how it was bound to fail.

Look for yourself:

PISA results through 2018

 

Source: https://www.oecd.org/pisa/publications/PISA2018_CN_USA.pdf

 

EDIT: I meant David Coleman the educational reform huckster, not Gary Coleman the actor!

 

How old is your dog in human years? The answer is as natural as falling off a log!

Or should I say a natural logarithm…

Some scientists studying mammalian genetics and methylation have concluded that it’s simply incorrect to multiply the actual age of a dog by seven to arrive at its human age: the relationship is not linear at all. Dogs mature much faster than humans, being fully able to have puppies of their own when they are one or two — which shows that the seven-to-one rule makes little sense there, even though that simple linear formula does more-or-less work when considering total life expectancies of us humans and our best friends.

They arrived at their conclusions, which were reported in Science, by drawing blood samples from over a hundred Labrador retrievers and comparing variations in markers on the DNA genomes thereof. I present a graph from the Arxiv preprint here, comparing a Labrador retriever with a well-known actor:

dog years

One of the formulas they came up with is the following

dog year eqwuation

which simply means that you take the natural logarithm (the one with base e, or about 2.718, which you may have studied in high school or college math classes, and which the calculator you have on your cell phone can do for you) of the dog’s age (D), multiply that by 16, and then add 31, to get the human age (D). That’s just about impossible to do in your head, so the Science writer provided a little calculator, which they warn is only valid for dog ages of 1 year or more.

I decided to play with the formula and make some tables so you can compare more easily a theoretical dog age to a theoretical human age, and decide for yourself if you think the study makes sense. I also calculated the inverse function (to go from human years to dog years directly, and got the following:

inverse exponential dog years

Here they are:

dog age table

Keep in mind that in the yellow part, the dog’s age is measured in months. (Yeah, I disregarded the warning about only using dogs aged 1 year or more!) And in the green part, a dog’s age is measured in years. Obviously, a one-month old puppy is not equivalent to a human baby that will only be born nine years in the future, but a lot of the rest does make sense.

Here is a pretty graph I made from the table on the left:

dog to human age converter graph

And from the one on the right:

human to dog age converter graph

Sharp eyed folks may have noticed that the equations produced by Excel don’t look like the ones I wrote. In the first case, the difference just comes from rounding. If you remember the rules of exponentiation, you may be able to figure out why mine looks almost completely different from the one Excel produced!

Published in: on November 18, 2019 at 10:14 pm  Leave a Comment  
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More Educational Miracles (Not!)

I have prepared charts and graphs for 8th grade NAEP average scale scores for black, hispanic, and white students in various jurisdictions: the entire nation; all large cities; Washington DC; Florida, Michigan; and Mississippi.

You will see that there was a general upwards trend in math from about 1992 to roughly 2007 or 2009, but the scores have mostly leveled off during the last decade. I included Michigan, since that is the state where current Education Secretary Betsy DeVos has had the mo$t per$sonal influence, but that influence doesn’t look to be positive.

While it’s good that DC’s black students no longer score the lowest in the nation (that would be Michigan – see the first graph), there is another feature of my fair city: very high-performing white students (generally with affluent, well-educated parents) in its unfortunately rather segregated public schools, as you can see in the last graph. Naep 8th grade math, black students, various placesnaep math, hispanic, 8th grade, various places

naep 8th grade math, white students, various places

Can You See The Educational Miracles in DC, Florida, Michigan, and Mississippi?

No?

Even though the Common Core curriculum is now essentially the law of the land (though well disguised), and nearly every school system devotes an enormous amount of its time to testing, and many states and cities (such as DC, Florida, and Michigan) are hammering away at public schools and opening often-unregulated charter schools and subsidizing voucher schemes?

You don’t see the miracles that MUST have flowed from those ‘reforms’?

naep reading 8th grade, black, nation, fl, dc, mi, ms, large cities

Neither can I.

I present to you average scale scores for black students on the 8th grade NAEP reading tests, copied and pasted by from the NAEP website for the past 27 years, and graphed by me using Excel. You will notice that any changes have been small — after all, these scores can go up to 500 if a student gets everything right, and unlike on the SAT, the lowest possible score is zero.

DC’s black 8th graders are scoring slightly lower than in 2013 or 2015, even though a speaker assured us that DC was an outstanding performer. Black Florida students are scoring lower than they did 2, 4, 6, or 10 years ago, even though Betsy DeVos assured us that they were setting a wonderful example for the nation. Michigan is the state where DeVos and her family has had the most influence, and it consistently scores lower than the national average. Mississippi was held up for us as a wonderful example of growth, but their score is exactly one point higher than it was in 2003.

Some miracles.

 

EDIT: Here are the corresponding charts and graphs for hispanic and white students:

naep, 8th grade reading, hispanic, various places

 

naep 8th grade reading, white students, various places

Not So Fast, Betsy DeVos!

I attended the official roll-out of the results of the 2019 National Assessment of Educational Progress (NAEP) a couple of days ago at the National Press Club here in DC on 14th Street NW, and listened to the current education secretary, Betsy Devos, slam public schools and their administrators as having accomplished nothing while spending tons of money. She and other speakers held up DC, Mississippi, and Florida as examples to follow. Devos basically advocated abandoning public schools altogether, in favor of giving each parent a “backpack full of cash” to do whatever they want with.

Some other education activists I know here in DC shared their thoughts with me, and I decided to look at the results for DC’s white, black, and Hispanic students over time as reported on the NAEP’s official site. (You can find them here, but be prepared to do quite a bit of work to get them and make sense out of them!)

I found that it is true that DC’s recent increases in scores on the NAEP for all students, and for black and Hispanic students, are higher than in other jurisdictions.

However, I also found that those increases were happening at a HIGHER rate BEFORE DC’s mayor was given total control of DC’s public schools; BEFORE the appointment of Michelle Rhee; and BEFORE the massive DC expansion of charter schools.

Here are two graphs (which I think show a lot more than a table does) which give ‘average scale scores’ for black students in math at grades 4 and 8 in DC, in all large US cities, and in the nation as a whole. I have drawn a vertical red line at the year 2008, separating the era before mayoral control of schools (when we had an elected school board) and the era afterwards (starting with appointed chancellor Michelle Rhee and including a massive expansion of the charter school sector). These results include both regular DC Public School students and the charter school sector, but not the private schools.

I asked Excel to produce linear correlations of the average scale scores for black students in DC starting in 1996 through 2007, and also for 2009 through 2019. It wasn’t obvious to my naked eye, but the improvement rates, or slopes of those lines, were TWICE AS HIGH before mayoral control. At the 4th grade level, the improvement rate was 2.69 points per year BEFORE mayoral control, but only 1.34 points per year afterwards.

Yes, that is a two-to-one ratio AGAINST mayoral control & massive charter expansion.

At the 8th grade level, same time span, the slope was 1.53 points per year before mayoral control, but 0.77 points per year afterwards.

Again, just about exactly a two-to-one ratio AGAINST the status quo that we have today.

pre and post Rhee, 4th grade NAEP, black students in DC, nation, large cities

pre and post Rhee, 8th grade NAEP, black students in DC, large cities, and nation

Charter schools do NOT get better NAEP test results than regular public schools

It is not easy to find comparisons between charter schools and regular public schools, partly because the charter schools are not required to be nearly as transparent or accountable as regular public schools. (Not in their finances, nor in requests for public records, nor for student or teacher disciplinary data, and much more.) At the state or district level, it has in the past been hard or impossible to find comparative data on the NAEP (National Assessment of Educational Progress).

We all have heard the propaganda that charter and voucher schools are so much better than regular public schools, because they supposedly get superior test scores and aren’t under the thumb of  those imaginary ‘teacher union thugs’.

However, NCES has released results where they actually do this comparison. Guess what: there is next to no difference between the scores of all US charter schools on the NAEP in both reading and math at either the 4th grade or 8th grade level! In fact, at the 12th grade, regular public schools seem to outscore the charter schools by a significant margin.

Take a look at the two graphs below, which I copied and pasted from the NCES website. The only change I made was to paint orange for the bar representing the charter schools. Note that there is no data available for private schools as a whole.

public vs charter vs catholic, naep, math

If you aren’t good at reading graphs, the one above says that on a 500-point scale, in 2017 (which was the last year for which we have results), at the 4th grade, regular public school students scored an average of 239 points in math, three points higher than charter school students (probably not a significant difference). At the 8th grade level, the two groups scored identically: 282 points. At the 12th grade, in 2015, regular public school students outscored charter school students by a score of 150 to 133 on a 300-point scale (I suspect that difference IS statistically significant). We have no results from private schools, but Catholic schools do have higher scores than the public or charter schools.

The next graph is for reading. At the 4th grade, charter school students in 2017 outscored regular public school students by a totally-insignificant 1 point (222 to 221 on a 500 point scale) and the same thing happened at the 8th grade level (266 to 265 on a 500 point scale). However, at the 12th grade, the regular public school students outscore their charter school counterparts by a score of 285 to 269, which I bet is significant.

charter vs public vs catholic, naep, reading, 2017

 

 

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