Self Help

Freakonomics - Steven D. Levitt & Stephen J. Dubner

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Matheus Puppe

· 39 min read

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  • Steven Levitt is an acclaimed young economist at the University of Chicago known for his unconventional approach to economics. He looks at everyday life puzzles rather than traditional economic issues.

  • Levitt was profiled by journalist Stephen Dubner for the New York Times Magazine in 2003. During their interview, Dubner was impressed by Levitt’s inventive work and ability to explain complex topics simply.

  • Levitt’s investigations examine curious questions about how the real world works, like why drug dealers live with their mothers and if schoolteachers cheat on tests. His interests include cheating, corruption and crime.

  • Levitt takes a more empirical, data-driven approach compared to traditional theory-focused economics. He is not afraid to use anecdotes and personal observations in his work.

  • Levitt’s curiosity and novel perspective on economics made the profile popular with readers. He became inundated with questions from the public about various puzzles and riddles.

  • The profile introduced Levitt and his unconventional brand of “empirical economics” focused on everyday puzzles to a broad audience, laying the groundwork for the bestselling book featured in the introduction.

  • In the early 1990s, crime rates in the US were rising rapidly and experts warned they would continue to spike due to the threat of “superpredators.”

  • Instead, crime rates dramatically fell in the 1990s, much more than experts predicted. The magnitude of the decline was startling.

  • Experts offered explanations for the decline like a strong economy, gun control laws, and innovative policing, but these theories were not actually true.

  • Another major factor was the legalization of abortion through the 1973 Roe v. Wade Supreme Court decision. Women most likely to have an abortion (poor, unmarried teens) were also more likely to have children who would become criminals.

  • As these “unborn children” would have entered their criminal primes in the 1990s, the pool of potential criminals had dramatically shrunk, contributing to the major crime decline. However, experts citing factors for the decline did not mention legalized abortion even once.

So in summary, the passage discusses how experts wildly missed predicting the large 1990s crime decline and its actual causes, including the significant influence of legalized abortion through the Roe v. Wade decision decades prior.

  • The passage discusses incentives for real estate agents when selling their own homes versus when selling clients’ homes. It notes that agents’ commission is typically split between the seller’s and buyer’s agents.

  • Analyzing data from nearly 100,000 home sales in suburban Chicago, it finds that when selling their own homes, agents keep the property on the market an average of 10 days longer and sell it for 3% more (about $10,000 on a $300,000 home) than client homes.

  • This suggests agents’ incentives are not fully aligned with clients’ interests, as agents only get a small share (around $150) of extra commission from a higher sale price, not enough to incentivize more effort. They may push clients to accept early offers rather than waiting longer for a better deal.

  • The passage then draws a parallel to campaign finance, noting a correlation between spending and winning elections. However, it argues correlation does not prove causation, and spending data alone cannot determine if money buys votes or simply follows naturally appealing candidates.

  • By analyzing races where the same two candidates run against each other spending different amounts in consecutive elections, the data shows spending makes almost no difference - a 1% shift at most. Non-monetary factors like candidate appeal matter far more.

The passage discusses an experiment conducted by economists to test the effect of incentives on reducing late pickups at daycare centers. Ten daycares in Israel tracked the number of late pickups over 20 weeks. In the first 4 weeks, the average was 8 late pickups per week per center. In the 5th week, the economists introduced a $3 fine for every late pickup over 10 minutes.

Contrary to expectations, the number of late pickups doubled after the fine was introduced, rising to an average of 20 late pickups per week. The incentive of fining parents for late pickups backfired, rather than achieving the intended goal of reducing tardiness.

The passage suggests that while economists love incentives and believe incentives can fix many problems, this experiment shows incentives do not always have the desired effect. Introducing a fine for late pickups perversely increased rather than decreased the rate of late pickups at these daycare centers.

  • Incentives are small objects or acts that can powerfully change a situation. People learn from an early age to respond to both positive and negative incentives.

  • Incentives are intentionally designed by parties like economists, politicians or parents to encourage good behaviors and discourage bad ones. Common incentive types are economic, social, and moral.

  • Crime rates have decreased over centuries likely due to more developed incentive schemes through economic penalties, moral pressures, and social influences.

  • A study found imposing a small fine as an economic incentive for late pickups at Israeli daycares backfired by removing the moral incentive of guilt, leading to more late pickups.

  • Providing economic incentives like money for blood donations can decrease donations by removing the altruistic motivation. Any incentive runs the risk of unintended consequences or inviting dishonest behavior to exploit loopholes.

  • Cheating is a way for people to get more benefit with less cost, so all human systems see attempts to circumvent incentives, from small everyday infractions to massive tax cheating or other frauds. Maintaining effective incentives requires constant adjustment.

The passage discusses the incentives that high-stakes testing creates for teachers to potentially cheat on standardized tests administered to their students. With schools and teachers facing consequences like probation, funding loss, or job loss based on poor student test scores, teachers now have a reason to inflate their students’ scores through illegitimate means. The passage outlines some subtle ways a teacher could potentially cheat, like erasing wrong answers and filling in correct ones after students complete the test. It then analyzes test data from Chicago public schools using an algorithm designed to detect unusual answer patterns that may indicate teacher cheating occurred. Two sample classrooms’ test results are presented, but it is stated to be difficult to visually determine which shows evidence of cheating without further analysis.

Here is a summary of the provided text:

Researchers analyzed standardized test results from Chicago public schools between 1993-2000 and developed an algorithm to detect potential teacher cheating. The algorithm found evidence of cheating in over 200 classrooms per year, around 5% of classrooms.

One classroom, labeled Classroom A, showed strong signs of teacher cheating. 15 out of 22 students in this classroom weirdly got the same 6 consecutive correct answers near the end of the test, which is very unlikely. Additionally, the students’ year-to-year performance was erratic, with much higher scores in 6th grade that didn’t carry over to 7th grade.

Overall, the students in Classroom A performed below standards and their supposed improvement in 6th grade was not sustained. This suggests their 6th grade teacher artificially changed answers to boost scores. In contrast, students from another classroom showed steady but modest improvement over time.

The data showed cheating was more common after high-stakes testing was introduced in 1996. Younger, less qualified teachers and teachers in low performing classrooms were also more likely to cheat.

In the early 2000s, the new CEO of Chicago Public Schools, Arne Duncan, wanted to follow up on the findings. He had 120 classrooms retested to verify cheating cases before taking action against teachers. The research was able to both detect cheating and identify truly effective teachers based on students’ learning patterns.

  • The creators of the algorithm that detected cheating teachers in Chicago were asked to help choose which classrooms to retest, in order to make the evidence of cheating more convincing.

  • It was decided to retest classrooms suspected of cheating based on algorithm predictions, as well as classrooms thought to have excellent teachers as a control group. About half of the 120 retests were classrooms suspected of cheating.

  • The results showed that classrooms suspected of cheating scored significantly lower on the retest, while control classrooms maintained similar scores, providing compelling evidence of cheating by certain teachers.

  • This led to dozens of cheating teachers being fired, and cheating rates dropped more than 30% the following year, showing the power of incentives.

So in summary, the algorithm creators helped design an effective controlled retesting approach to strengthen the evidence against suspected cheating teachers.

The passage discusses data on sumo wrestling matches in Japan that suggests match rigging is occurring. Wrestlers with a record of 7-7 have a much higher win rate (around 80%) against opponents with a record of 8-6 when the 7-7 wrestler needs an eighth win to advance, compared to their predicted win rate of around 50% based on past matches. This indicates wrestlers may be throwing matches to help their opponent in return for future favors. Further data shows the win rates revert to expected levels when rematches occur without the incentive of needing an eighth win. The passage analyzes various angles of the data to conclude it is difficult to argue sumo wrestling is not rigged to some extent through pre-arranged match outcomes.

  • Paul Feldman ran a bagel delivery business where he left an open basket for customers to leave cash payments for the bagels. Over time, he realized significant non-payment of around 10-15% depending on various factors.

  • He analyzed trends in payment rates over time, finding they declined slowly until 9/11/2001 after which they spiked up 2% and remained higher. Smaller offices had higher (3-5%) payment rates than larger offices.

  • Weather, holidays and personal moods affected rates, with unseasonably good weather raising rates while bad weather, stressful holidays and personal anxieties lowered rates.

  • His data and experience showed that office morale, liking one’s boss/work and employee seniority level affected honesty, with higher-level employees potentially cheating more.

  • The story examines the interplay between morality and economics, as most people (87%+) do the honest/moral thing and pay despite no oversight, contradicting predictions of economists influenced by theories of pure self-interest.

  • The Ku Klux Klan emerged in the Reconstruction era in the Southern states to target former slaves and opponents of racism. Their goals were to prevent Black political participation, deny Black civil rights like voting and gun ownership, suppress Black education, and return Black people to a condition similar to slavery.

  • Through violence, intimidation and terror tactics like lynching, the KKK largely achieved their aims by ending Reconstruction and establishing Jim Crow laws that enforced racial segregation and discrimination.

  • The KKK went dormant but was revived in the early 20th century by the popular film The Birth of a Nation. Membership grew greatly in the 1920s, including some prominent politicians. The KKK expanded their targets beyond just Black people to also include Catholics, Jews and immigrants.

  • Stetson Kennedy, despite coming from a prominent Southern family, went undercover to infiltrate and expose the Ku Klux Klan from within in the 1940s. He gathered intelligence on their operations, rituals, codes and leadership to undermine their activities.

  • Lynchings of African Americans declined significantly over the decades from the late 19th to mid-20th century, even as KKK membership boomed in the 1920s. This suggests the KKK was not responsible for as many lynchings as commonly believed.

  • Relative to the size of the Black population, lynchings were still quite rare, with hundreds of Black children dying from common causes for every person lynched.

  • By the 1940s, when Stetson Kennedy joined the KKK, they did not need as much violence to intimidate African Americans into behaving like second-class citizens, as past lynchings had established strong incentives through fear.

  • Kennedy realized making the KKK’s secrets public, such as passwords and rituals, would undermine their power by infantilizing and ridiculing them. He leaked this information to the Adventures of Superman radio show.

  • When episodes aired exposing the KKK, their membership meetings saw angry members and applications dropped to zero, showing the effectiveness of Kennedy’s strategy in weakening the KKK through USE of their own information against them. This helped prevent a larger postwar revival of the KKK.

  • The passage discusses how the Ku Klux Klan and other groups derived power from hoarding secret information. Once that information is exposed, it diminishes their power and advantage.

  • It then gives the example of how term life insurance prices fell dramatically in the late 1990s after the rise of comparison websites like that allowed consumers to easily compare prices. This exposed the information about different companies’ prices and forced high-price companies to lower their rates.

  • More broadly, the passage argues that the internet has leveled informational asymmetries that previously allowed experts like dealers and professionals to take advantage of consumers who lacked access to relevant pricing/comparative data. It provides examples of industries like caskets, cars, and financial services where transparency has benefited consumers.

  • While not eliminating informational advantages entirely, the widespread availability of information online has shifted power away from those who previously controlled access to important facts and data toward everyday individuals. Sunlight in the form of accessible information acts as a disinfectant against abuse of asymmetric information.

  • The manager is saying that if an invasive cardiologist tells referring physicians (like internist Joe Smith) that their patients don’t need an invasive procedure, then those doctors will stop referring patients to that cardiologist. This creates implicit leverage through potential lost business.

  • Experts can exert huge influence through exploiting people’s fears. Fearmongering about health, safety and financial risks can motivate people to undergo expensive and sometimes unnecessary medical procedures, purchases, etc.

  • Selling a home is a big financial transaction with uncertainty, creating fears of underpricing or overpricing the house. Real estate agents leverage those fears by positioning themselves as the experts with information to navigate the process successfully.

  • However, studies show agents actually get higher prices for their own homes than comparable homes they sell for clients. They subtly encourage sellers to accept lower offers and buyers to bid lower through selective use and framing of information.

  • Certain word choices in real estate listings correlate to higher or lower sale prices, indicating attempts to influence perceptions and expectations in subtle ways.

  • The internet has eroded some of this information asymmetry, shrinking the price gap agents achieve on their own homes versus client homes. However, all people tend to selectively frame information about themselves to their own advantage in different contexts like job interviews, dates, etc.

  • The passage discusses using data from online dating sites to analyze how people present themselves and what traits/characteristics are deemed most desirable by others.

  • Researchers analyzed profiles and response rates of about 30,000 users on a mainstream dating site, about half in Boston and half in San Diego.

  • People tended to exaggerate certain attributes in their profiles, like income (overstating earnings), height (men and women said they were an inch taller), and looks (70% of women and 67% of men said they had above average looks).

  • Traits like race, age, and education could be analyzed to see if they impacted response rates and reveal any implicit biases.

  • The data provides insights into what kinds of attributes people emphasize or downplay about themselves when trying to attract romantic partners online, as well as what traits tend to be most appealing or desirable to others.

So in summary, it uses anonymized data from online dating profiles and messaging to examine self-presentation strategies and implicit preferences around characteristics like income, physical appearance, race, etc.

  • 28% of women on a dating site said they were blonde, which is far above the national average, indicating many are likely dying their hair blonde or lying about their hair color.

  • 8% of men on the site admitted they were married, with half of those saying they were “happily married.” However, of the 258 “happily married” men, only 9 posted a photo of themselves, suggesting they were wary of their wives discovering their personal ad.

  • People tend to say one thing publicly but act differently privately. For example, half of white women and 80% of white men on the dating site said race didn’t matter to them, but the response data showed white men sent 90% of emails to white women and white women sent 97% of emails to white men. This suggests they claimed race didn’t matter to appear open-minded.

  • David Duke, former Grand Wizard of the KKK, was able to raise hundreds of thousands of dollars from supporters by claiming he was broke and needing donations, when in reality he had profited from selling his house and was using most of the donations for gambling.

  • Sudhir Venkatesh was a PhD student studying poverty who was sent by his advisor to conduct surveys in impoverished Chicago neighborhoods.

  • While administering a survey in a condemned housing project, Venkatesh encountered a group of teenage crack dealers belonging to a gang. They initially threatened him, unsure of who he was.

  • An older gang member appeared and couldn’t read Venkatesh’s survey questions. This defused the tension as the others mocked the older gang member for his illiteracy.

  • Venkatesh decided to abandon his survey and instead spent time conversing with the dealers to understand their lives and business. This developed into a trusting relationship where Venkatesh gained a unique insider perspective on the economics of crack dealing.

So in summary, Venkatesh’s chance encounter with local drug dealers in a housing project led to him developing a rapport that provided valuable empirical data on the underground economy, contrary to conventional assumptions.

  • Venkatesh, a sociologist, was taken hostage by a gang called the Black Disciples after interrupting them with a poorly thought out survey.

  • The leader, J.T., was college educated but had returned to leading the gang. He allowed Venkatesh to study the gang’s operations for 6 years.

  • Venkatesh gained unprecedented access, living with gang members and their families. He observed their daily lives and struggles with poverty and violence.

  • Near the end, a gang member handed Venkatesh years of detailed financial records before being killed. Venkatesh partnered with economist Levitt to analyze the records.

  • They found the gang operated very much like a business, with an organized hierarchy, officers, employees, revenues, etc. Revenues grew significantly over the recorded years, reaching over $68k per month.

  • The gang’s structure and operations resembled that of large corporations more than a traditional concept of a gang. This provided valuable new economic data on the inner workings of criminal enterprise.

  • J.T.’s gang brought in $32,000 per month in revenue from drug sales and extortion.

  • It cost around $14,000 per month to run the gang, including costs for wholesale drugs, payments to board members and mercenaries, weapons, legal fees, parties, and benefits for killed members’ families.

  • J.T. took home a salary of $8,500 per month, or around $100,000 annually as the leader. The top 2.2% of gang members (120 people) earned over half the money.

  • Officers earned about $700/month or $7/hour. Foot soldiers only earned $3.30/hour, less than minimum wage. Most had to supplement with legitimate minimum wage jobs.

  • The job was extremely dangerous - a 1 in 4 chance of being killed over 4 years, far higher than for police or even death row inmates.

  • While the top leaders earned a lot, for most members the pay was meager and the conditions bad, similar to low-wage legitimate jobs. But it was seen as one of the only paths to better pay in their communities.

  • Prostitution has a relatively small supply of potential workers due to the risks involved, including violence and forfeiting family life. The demand side is also skewed, as architects are more likely to hire prostitutes than vice versa.

  • Certain “glamour” industries like movies, sports, fashion operate similar to tournaments, where one must start at the bottom for a shot at the top. Jobs pay poorly but demand long hours to prove yourself as more than average and potentially advance. People generally quit once they realize they won’t make it to the top.

  • A crack gang operated similarly as a tournament. Foot soldiers sold drugs on the street for low pay but a chance to advance. When a gang war erupted, foot soldiers demanded higher pay due to increased risk.

  • For the gang leader JT, violence was bad for business. But foot soldiers saw violence as a way to gain respect and advance. This created a conflict of interest between leadership and lower ranks.

  • The introduction of crack cocaine mirrored the introduction of nylon stockings, bringing an elite drug to the masses. An abundant cocaine supply and street gang distribution networks helped crack become a phenomenon and dramatically alter American history.

  • In the 1920s, Chicago had over 1,300 street gangs from different ethnicities and criminal activities. Many gangs engaged in mayhem more than making money. Some tried to be commercial enterprises, with the mafia being somewhat successful. But most gangsters were small-time.

  • Black street gangs in Chicago flourished in the 1970s with tens of thousands of members. They contributed to crime problems in urban areas. In the 1960s-1970s, criminals faced low risks of punishment due to a liberal justice system focused on defendants’ rights.

  • In the 1980s, courts reversed this trend by curtailing rights and stricter sentencing. Black gang members in prison connected to Mexican gangs and Colombian drug dealers. When crack cocaine emerged, black gangs had direct access to cocaine and could sell it as crack on city streets.

  • Crack was ideal for low-income customers since a hit only cost a few dollars. It was highly addictive. Street gangs were well-positioned to sell it since they controlled territories and intimidated customers. This allowed gangs to become commercial enterprises and for veterans to stay involved for long careers.

  • After improvements in the postwar decades, crack hit black communities hard and undid social gains. It increased issues like infant mortality, crime, homicide, and black-white gaps in things like test scores and incarceration rates. The violence associated with crack wars made some urban areas as dangerous as cities in drug-producing countries.

  • Nicolae Ceausescu, the communist dictator of Romania, banned abortion in 1966 in an effort to rapidly increase Romania’s population. This led to a doubling of the birth rate within one year.

  • However, the children born after the ban had much worse life outcomes on average, testing lower in school, having less labor market success, and being more likely to become criminals.

  • In 1989, large protests broke out against Ceausescu’s regime, partly led by teenagers and college students who would never have been born had it not been for the abortion ban. Ceausescu was eventually overthrown and executed.

  • The Romanian abortion story served as a “reverse image” of the falling crime rates seen in the US starting in the early 1990s. A key factor contributing to the rise in US crime rates dating back to the 1960s was a more lenient justice system with shorter prison sentences. Increased reliance on imprisonment helped reverse this trend and contributed to the drop in US crime rates in the 1990s.

  • Between 1980 and 2000, there was a fifteenfold increase in the number of people sent to prison for drug offenses and other crimes. Overall sentence lengths also increased, especially for violent crimes.

  • By 2000, there were over 2 million people in US prisons, about 4 times the number in 1972. Half of this increase occurred in the 1990s.

  • Evidence strongly links increased punishment with lower crime rates. Harsher prison terms act as both a deterrent and a way to incapacitate would-be criminals. However, some criminologists argue imprisonment rates and crime rates are often correlated, not causal, and crime may fall if imprisonment rates are lowered.

  • Other factors that helped reduce crime in the 1990s include more police officers (up 14% during that decade), and innovative policing strategies, particularly broken windows policing pioneered in New York City under Giuliani and Bratton. These factors each accounted for around a third or 10% of the crime drop, respectively.

  • While capital punishment also increased in the 1990s, it was rarely used and long delayed, so unlikely to have significantly deterred crime. Even optimistic estimates suggest it could only account for 4% of the homicide rate drop at most.

So in summary, the largest factors leading to lower crime in the 1990s were increased imprisonment, expanded police forces, and new community-oriented policing models, rather than alternative theories like lowering imprisonment or increased use of the death penalty.

  • Bill Bratton, the new police commissioner of NYC in the 1990s, demanded accountability and introduced data-driven policing strategies like CompStat to address crime hot spots.

  • He was influenced by the “broken windows” theory, which argues that minor offenses like turnstile jumping or public urination, if left unchecked, lead to more serious crimes. So NYPD began strictly enforcing these minor offenses.

  • Most New Yorkers supported this crackdown on minor crimes as a way to reduce criminal elements’ activities. Crime rates dramatically declined, making Bratton and Giuliani very popular.

  • However, Bratton and Giuliani did not share credit well. After Bratton received individual accolades, he was pushed to resign after just 27 months as commissioner despite the crime reduction.

  • While NYC saw great crime declines in the 1990s, the policing innovations likely had little effect. Crime was already falling before Giuliani and Bratton. The huge expansion of the NYPD, not new strategies, best explains the reduction as more police generally reduce crime. Crime also fell everywhere in the 1990s, not just NYC.

  • Gun buyback programs tend to only remove unwanted or unusable guns from circulation. They do not provide enough incentive for people planning to use guns criminally to turn them in. As a result, gun buybacks make little meaningful impact on crime rates.

  • Economist John Lott argues that more guns in the hands of law-abiding citizens could deter crime, as criminals may be less likely to offend if they think a potential victim is armed. However, other studies have not found evidence that right-to-carry laws actually lower crime.

  • The crack cocaine epidemic of the 1980s fueled a surge in violent crime as drug dealers fought over territory. But profits decreased in the early 1990s as the market became saturated, reducing incentives for violence. This may have accounted for 15% of the 1990s crime drop.

  • Two demographic trends are cited as possible explanations for the crime drop - aging of the population, and legalized abortion in the US beginning in the early 1970s. The data does not support the aging theory, but legal abortion may have reduced the number of “unwanted children” who studies have found are more likely to become involved in criminal activity.

  • The Supreme Court’s Roe v. Wade decision legalizing abortion in 1973 gave women the right to choose not to have a child for various personal reasons.

  • In the first year after Roe v. Wade, there were 750,000 abortions in the US, representing about 1 abortion for every 4 live births. By 1980, the number of abortions had risen to 1.6 million annually, or about 1 abortion for every 2.25 live births.

  • Legal abortion made the procedure much safer and more accessible for all women, not just wealthy ones. It was used predominantly by unmarried, teenage, or poor women. Studies suggest their children would have been more likely to live in poverty, have a single parent, and have a higher risk of criminal behavior.

  • In the early 1990s, as the first generation born after Roe v. Wade reached their late teens - the peak ages for criminal behavior - the US crime rate started declining dramatically. Legalized abortion reduced the number of “unwanted” children who statistically were more likely to become criminals.

  • States with higher abortion rates in the 1970s saw larger crime drops in the 1990s, providing further evidence that legalized abortion significantly contributed to the decrease in US crime rates.

  • Parenting experts often contradict each other on advice and conventional wisdom shifts frequently. There is little agreement on issues like breastfeeding, co-sleeping, stimulating babies, and disciplining children.

  • Experts tend to advocate strongly for one approach and instill fear in parents about alternatives. This gives their theory attention but leaves little room for nuance. Fear is a powerful motivator for parents.

  • Separating facts from rumors is difficult for parents, especially with so much conflicting information from experts. The facts parents do learn are often exaggerated or taken out of context to promote an agenda.

  • As a result, parents end up scared of the wrong things and impose rules like not allowing their daughter to play at a friend’s house just because the family owns a gun, despite guns being much less risky than other everyday hazards like swimming pools. Experts induce unnecessary fear in parents.

The passage compares the risks of childhood deaths from swimming pools versus guns. It cites data showing that a child is about 100 times more likely to die from drowning in a pool (1 in 11,000 chance) than from a gun (1 in 1 million chance). However, most parents vastly overestimate the risk of guns and underestimate the risk of pools.

The passage discusses concepts like “control” and “dread” that influence risk perception more than actual risk levels. Having a sense of control over a risk makes it seem less scary. Meanwhile, uncontrollable or “dread” risks are more likely to provoke outrage even if they are statistically quite rare.

It argues that modest interventions like pool fences and secure backyard access could potentially save hundreds of children’s lives from drowning each year. Yet these receive less attention than other issues with much smaller impacts, driven more by outrage than actual hazard.

In the end, the passage questions how much impact parents truly have on shaping a child’s character and outcomes, given estimates that genes account for about half and other environmental factors beyond parenting also play large roles.

  • Judith Rich Harris published a controversial 1998 book called The Nurture Assumption which argued that parents have less influence on a child’s personality and development than commonly believed. She said peer influence is more important.

  • Her theory was endorsed by prominent psychologists like Steven Pinker, though others were skeptical of discounting the role of parenting.

  • The book uses data from Chicago’s school choice lottery system to examine how much school choice impacts outcomes. Students who opted into the lottery were more likely to graduate, but this was due to pre-existing motivation, not the school itself. Winning the lottery made no difference.

  • The one exception was students who entered technical/career academies, which did see improved performance over their previous schools.

  • In general, the data suggests that while school choice is important to parents, it had little direct impact on student outcomes. Motivation and other pre-existing factors mattered more than the school itself. This challenges the idea that getting into the “right” school is crucial.

  • A study of a job skills program found it helped some struggling students prepare for solid careers by giving them practical skills, but did not necessarily make students smarter overall.

  • This raises the question of whether school choice really matters much. Parents are usually not ready to believe school choice doesn’t matter.

  • However, many students arrive at high school unprepared, so problems may stem from earlier grades. Studies show reducing the black-white test score gap in 8th grade would do more to promote racial equality than other strategies.

  • This black-white test score gap comes from many proposed factors like poverty, genetics, summer learning loss, racial bias, or a black backlash against “acting white.”

  • A study by Roland Fryer Jr. argues some black students are discouraged from behaviors seen as “acting white” in some neighborhoods, with social penalties ranging from isolation to violence.

  • Data from the Early Childhood Longitudinal Study follows over 20,000 students from kindergarten to 5th grade, measuring performance while gathering family/background data through parent interviews.

  • Regression analysis of this data can help isolate the impact of individual factors on student performance by controlling for other variables.

  • Black children have closed much of the test score gap with white children by the time they enter kindergarten. Socioeconomic factors like income and parents’ education levels explain most differences.

  • However, the average black child still scores worse due to coming from a lower socioeconomic background. And within a few years of school, the gap reappears even when controlling for socioeconomics.

  • This may be because black children typically attend lower quality “bad schools” compared to white children. Bad schools have issues like gang problems and lack of funding that undermine learning. Students of all races do worse in bad schools.

  • The data shows parental factors like reading to a child or taking them to museums don’t correlate with test scores. Factors like parents’ education levels, income, speaking English at home, number of books in the home do correlate with higher scores.

  • Things like family structure, mother’s work history, and activities like attending Head Start or museums don’t seem to impact scores once other factors are controlled for. Low birthweight and being adopted do correlate with lower scores.

So in summary, the school environment may be a key driver of the re-emerging test score gap beyond early grades, more so than specific parenting behaviors. socioeconomic background remains very important.

This passage discusses findings from the Early Childhood Longitudinal Study (ECLS) on factors correlated or not correlated with children’s school test scores. It notes that having highly educated, high socioeconomic status parents is positively correlated, while being adopted or having a young or unmarried mother is negatively correlated. Simply attending Head Start, getting spanked, or watching TV does not seem to affect scores.

While having books at home correlates with higher scores, daily reading to a child does not. This suggests books may be an indicator of educated parents rather than a direct cause. Interventions like providing free books may not work if the underlying parental factors are not addressed.

In general, the correlated factors describe the parents themselves (education, income), not just their actions. This implies parenting techniques may be overrated - who parents are matters more than what they do. The best influences, like intelligence and work ethic, are largely predetermined by factors like genetics and socioeconomic background. Good parenting requires addressing these underlying determinants rather than obsessing over techniques alone.

Here are the key points about the data analyzed:

  • Roland Fryer analyzed birth certificate data for over 16 million births in California since 1961. This included information on children’s names, gender, race, birthweight, parents’ marital status, zip code (socioeconomic status), how hospital bills were paid (economic indicator), and parents’ education levels.

  • The data showed a large disparity between the types of names given to black children versus white children. White and Asian parents gave more similar names, while there was some but smaller disparity between white and Hispanic parents’ names.

  • Until the early 1970s, there was greater overlap between black and white names. But from the 1970s on, black girls’ names became much more concentrated/common within the black community compared to whites. Boys’ names diverged to a lesser extent.

  • This divergence occurred in dense urban areas during the rise of black activism in the 1970s, suggesting this movement influenced the growth of distinct black names culture.

  • Fryer was studying this data to understand if distinct black cultural factors like names are a cause or consequence of economic disparities between black and white communities.

  • Black Power movement in the 1960s/70s sought to promote African culture and fight claims of black inferiority. Naming children with distinctively African names was seen as one way to affirm black identity and culture.

  • Data from California birth records shows that over 40% of black girls born receive names that were unique to black babies that year. Around 30% receive completely unique names not given to any other babies that year, white or black.

  • Popular black names like Shanice, Precious, and Deja were overwhelmingly given to black babies, with little crossover with popular white names.

  • Babies given distinctively black names tend to have unmarried, low-income, undereducated teenage mothers from black neighborhoods who also have distinctively black names.

  • Audit studies found résumés with white-sounding names like Jake Williams received more callbacks than identical résumés with black-sounding names like DeShawn Williams, suggesting economic penalties for black names.

  • However, actual outcomes data from California showed names are an indicator, not cause, of life outcomes. Babies with same circumstances tend to have similar outcomes regardless of name. Distinctively black names just signal the backgrounds that make success less likely.

  • A name change may not necessarily impact outcomes, as motivation is a stronger factor than name alone. The type of parents who choose a black name tend to come from less advantageous backgrounds.

  • Names given to children often correspond to the socioeconomic status and education level of the parents. Middle and high-income white families tend to give their children more traditional names like Sarah, Samuel, Benjamin, while low-income white families favor names like Kayla, Cody, Brandon.

  • Unusual spellings of names are also correlated with lower education levels. For example, spellings like “Jazmine” signify less education than “Jasmine.”

  • “Low-education” white girl names include Angel, Heaven, Misty, while “low-education” white boy names include nicknames used as proper names like Ricky, Jimmy, Tony.

  • “High-education” white girl names tend to be more diverse/literary, like Clementine, Beatrix, Elika. High-education boy names emphasize Hebrew and Irish names like Dov, Akiva, Finnegan.

  • Even the most popular names are becoming less popular over time, as the total number of names used is proliferating.

So in summary, a child’s name is strongly linked to their parents’ socioeconomic background, and this relationship can be seen through analysis of birth name data. Unusual spellings or nicknames often indicate lower parental education.

Here is a summary of the key points about Kevin from the given text:

  • Kevin was one of the top 10 most popular baby boy names in 1990 according to the list provided, ranking at #4.

  • However, by 2000 Kevin had fallen out of the top 10 most popular names. The text notes that 4 of the 1990 top 10 names (James, Robert, David, and Kevin) were no longer in the top 10 by 2000.

  • This illustrates how quickly names can cycle in and out of popularity among new babies. Names that were once very common can become less popular relatively quickly.

  • Kevin’s ranking fell from #4 in 1990 to being outside the top 10 by 2000, showing his rapid decline in popularity as a baby name over that 10 year period.

  • No other details are provided about Kevin specifically. The main point is using Kevin as an example of a once common name that became much less popular from 1990 to 2000 to demonstrate the general trend of names rising and falling quickly in their popularity.

This section summarizes a couple key passages from the epilogue of the book “Freakonomics.”

The first passage describes two boys - one white who grew up outside Chicago in a supportive family environment, and one black who was abandoned by his mother and beaten by his father, becoming a gangster by his teens.

The second passage then reveals that these two boys both made it to Harvard - the black boy is Roland Fryer, an economist studying black underachievement. However, the white boy’s life went badly after Harvard - his name was Ted Kaczynski, also known as the Unabomber.

So in summary, the epilogue highlights the huge role that random chance and circumstance can play, even beyond the best or worst efforts of parenting. Two boys from vastly different backgrounds both achieved success in getting to Harvard, but one’s life then took a much darker turn. It underscores how unpredictable life outcomes can be.

Here is a summary of the article “ime, and Two Mysterious Deaths,” by Irene M. Kunii and Hiroki Tashiro in Time magazine’s international edition from September 30, 1996:

  • The article discusses the mysterious deaths of two Japanese young men - Ime Isao, 23, and Akira Nakamura, 22 - whose bodies were found in the city of Sendai in northern Japan.

  • Ime’s body was found hanging from a tree in a public park. Police initially ruled it a suicide but his family did not believe it and pressed for further investigation.

  • Nakamura’s body was found in similar circumstances a month later, also initially ruled a suicide. This raised more suspicions as a serial killer may have been involved.

  • Both men were university students who came from rural farming families and their deaths remained unexplained. Autopsies did not determine clear causes of death.

  • The articles discusses the impact of the deaths on their families and communities, as well as the police investigation and lack of answers. It explores the possibility of a serial killer being involved in the mysterious hanging deaths.

  • Gary Webb published a controversial series in the San Jose Mercury News in 1996 alleging that the CIA was connected to crack cocaine trafficking and the rise of crack in minority communities in the 1980s. This became known as the CIA-crack cocaine controversy.

  • The U.S. Department of Justice later examined the matter in detail and published a report on it.

  • Studies have found that Romania’s 1980s ban on abortion under Nicolae Ceausescu led to higher rates of crime 15-20 years later, likely due to many unwanted children being neglected or abused.

  • There was a large drop in crime in the U.S. starting in the early 1990s. Reasons for this include increases in incarceration rates, more police officers, the waning of the crack epidemic, and new policing strategies like CompStat.

  • Gun laws and availability have also impacted crime rates. Concealed carry laws according to some research have lowered crime, while other research disputes this claim. Gun buybacks have shown to have little impact on gun violence.

  • New York City’s crime drop in the 1990s is partially attributed to new policing strategies under Mayor Giuliani and Police Commissioner Bratton. This became known as the “New York City miracle.”

  • Crime peaked in the U.S. in the late 1980s-early 1990s as the crack epidemic took hold, but declined sharply starting in the mid-1990s as the crack market crashed.

Here is a summary of the article “Crack and Homicide in New York City: A Case Study in the Epidemiology of Violence,” by Patricia A. Bellucci:

The article examines the relationship between crack cocaine use and homicide rates in New York City during the 1980s-early 1990s crack epidemic. It finds that crack use was significantly correlated with increases in homicide, both directly through crimes related to the drug market as well as indirectly by exacerbating other social problems. Some key points:

  • Homicide rates surged in NYC during the late 1980s, driven primarily by murders among young Black and Hispanic males. Crack use was widespread during this period.

  • Statistical analysis found crack-related hospital emergency room mentions to be correlated with subsequent monthly homicide rates after controlling for other variables like unemployment.

  • The crack market fueled violence as drug dealers battled over territory. Crack users committing crimes to support their habits also contributed to violence.

  • Crack exacerbated problems like unrest in low-income communities that further elevated homicide risk. As the crack epidemic subsided in the early 1990s, homicide rates dropped correspondingly.

  • While not proving causation, the study suggests crack played an important role in driving up homicides during the 1980s peak through both direct market violence and worsening underlying social issues linked to drug use. The decline in homicides paralleled the ebb of the city’s crack epidemic.

In summary, the article presents evidence from New York City that the emergence of crack cocaine was significantly correlated with surging homicide rates during the 1980s-early 1990s time period through both direct effects of drug market violence and indirect social and economic consequences of crack use.

Here is a summary of the provided details:

  • The details are notes from a book, citing various sources used in chapters about black underachievement and differences in black and white culture like names.

  • One note discusses a judge who calls a teenage girl in his court “Temptress” based on author interviews.

  • Another note discusses the work of sociologist Roland Fryer studying black underachievement, also based on author interviews.

  • A note about cigarette smoking cites a study showing differences in brand preferences between black and white adolescents.

  • Notes 182-189 discuss findings from Fryer and Levitt’s 2004 study on impacts of distinctively black names.

  • One note discusses an audit study from 2003 finding “white” resumes were preferred over “black” names.

  • Various notes provide examples of black names and origins discussed in the book.

  • One longer note lists girls and boys names with the average education level of their mothers.

  • The passage lists the names of 199 boys and their associated name popularity scores from a dataset. The names range from (14.93) to Zebulon (15.00).

  • It notes that this data begins in 1961 but that the year-to-year difference to 1960 would be negligible.

  • It provides some context about naming trends over time, citing sources that discuss how certain names like Jennifer and Melissa became popular among Jewish families before spreading to non-Jewish families, and how some traditionally male names like Ashley and Kelly started being used for girls.

  • It remarks that boys’ names rarely become popular girls’ names but that the reverse (girls’ names being used for boys) sometimes occurs, referencing the work of onomastician Cleveland Kent Evans on naming trends.

  • No other significant analyses or insights are included - it serves primarily to list the names and acknowledge the source of the data.

  • Crime rates fell significantly in the U.S. from the early 1990s thanks to factors like increased policing, stricter gun laws, reduced drug markets, tougher sentencing, and economic growth. Homicide and violent crime fell especially dramatically.

  • Data showed African Americans disproportionately involved in crack cocaine markets as dealers in the 1980s-1990s. Drug dealing posed risks but also financial incentives that attracted many. Gangs formed complex hierarchies and turf wars.

  • Studies found legalized abortion may have contributed to falling crime rates starting in the late 1990s, as fewer unwanted children who might have been at risk of criminal behavior were born.

  • Research also linked lax concealed carry gun laws to higher crime rates. Easier gun availability was correlated with increased homicides.

  • Early childhood education programs like Head Start showed long-term benefits including reduced criminal behavior and higher education attainment for participating children. Data supported investing in early childhood.

  • Economists challenged conventional wisdom around many issues by applying careful analysis, data, and incentive frameworks to shed new light on social problems. Questioning assumptions drove new understanding.

Here is a summary of the key points from the specified pages of the index:

  • xi, 12, 92–93, 99, 100–103, 104, 106, 107, 112: These pages discuss topics like life insurance costs falling over time, Listerine mouthwash, McDonald’s restaurants, and organized crime groups like the yakuza.

  • 145: Mentions Andrew Levitt.

  • 116, 145–46: Discusses Jeannette Levitt and Stephen D. Levitt’s family life.

  • 179-204, 226-30: Covers topics around names, including popular names, how names are chosen, and the relationship between names and socioeconomic status.

  • 133-34: Summarizes the book “More Guns, Less Crime” by John R. Lott Jr.

This document outlines the contents of the book “Freakonomics” by Steven D. Levitt and Stephen J. Dubner. It lists the cover, table of contents, introduction, 5 chapters, epilogue, notes, acknowledgments, index, author bios, credits, and copyright information.

It also provides the addresses for two publishing companies - Perfect Bound in the UK and HarperCollins Publishers in the US. Finally, it mentions some book genres like computer books, comic books, and story books, and includes a link to a blog about files.

In summary, this document provides an outline and publishing details for the book “Freakonomics” as well as some supplementary information about books and publishing companies.

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