New York

CSA, UFT spar over Bronx barricading, until a Web site is revealed

New York

What Counts as a Big Effect? (I)

I woke up yesterday morning to read Norm Scott's post on Education Notes Online about a new study of the effects of charter schools on achievement in New York City.  The study, by economists Caroline Hoxby and Sonali Murarka, finds a charter school effect of .09 standard deviations per year of treatment in math and .04 standard deviations per year in reading.  I haven't read the study closely yet, but I was struck by Norm's headline:  "Study Shows NO Improvement in NYC Charters Over Public Schools."  The effects that Hoxby and Murarka report are statistically significant, which means that we can reject the claim that they are zero.  But are they big?  That's a surprisingly complicated question. I'm going to argue that the answer hinges on "compared to what?" The standard deviation is a basic measure of how spread out a given attribute—such as a test score—is in a population.  When scores are widely spread out away from the average, the standard deviation is large;  when the scores are narrowly bunched around the average, the standard deviation is small.  Many distributions, whether in nature or by design, take on the shape of a bell curve.  The family of such distributions are called normal distributions, and they have some properties that are really useful for making sense of a given effect. The figure below shows a standard normal distribution, with a mean of zero and a standard deviation of one.  A standard normal distribution is symmetric, with 50% of the cases above the mean and 50% below the mean.  About 34% of the cases are between the mean and one standard deviation above the mean, and a similar fraction is between the mean and one standard deviation below the mean.  An additional 13% on each end or so are between one and two standard deviations away from the mean, and about 2.5% on each are more than two standard deviations away from the mean.
New York

Charter schools will get $30M in one-shot plan to counter freeze

PHOTO: Alan PetersimeA Queens charter school encouraged parents and students to call Governor David Paterson and Senate Majority Leader Malcolm Smith after it learned charter schools could see their funding frozen. Paterson and Smith are now sending the schools $30 million. (##http://picasaweb.google.com/teach11372/RenaissanceCharterRallyAndMarchAgainstCharterCuts#5319497282636828866##Nicholas##) Governor David Paterson and Malcolm Smith, the state Senate majority leader, are back in good favor with their long-lost charter school friends. Smith has just announced a plan to counteract a budget freeze that took the schools by surprise earlier this year, by sending the schools a one-time $30 million grant. The grant is less than the $51 million that charter schools were slated to lose after legislators axed planned funding increases in their recent budget deal. And it will expire at the end of next year, leaving supporters to wage a new fight  over funds then. But a source familiar with the plan who is a supporter of charter schools said that $30 million will be enough to help schools that had been imagining slashing after-school programs and turning down extra staff they'd already hired for next year. Smith announced the planned injection just now at a charter school lottery in Harlem, which Philissa is covering. The lottery is the annual event for the former City Council member Eva Moskowitz, who runs the Success Charter Network in Harlem. Harlem Success is expecting more than 5,000 parents at the lottery, which will determine which children are selected to attend the schools.