9.4: Group Differences in IQ: The Science and

There is a claim that a product can increase IQ scores.

Correlation and Causation are extraordinary.

There are no references to the peer-reviewed 3 in the ad.

In principle, the claim that Supersynapse's products boost IQ could be false.

One would need to compare 6.

There may be more parsimo to eliminate the possibility of placebo effects, as well as other explanations for the reported effects of Supersynapse, such as the amount of time and effort on the tasks.

There was a summary emerging across multiple studies.

That's good news.

The ad acknowledges the claims.

The claims in the ad are remarkable, but the evidence was done in-house by scientists working for the company, who are likely to be biased towards the details.
There is no way for consumers to consult uct.
It's important that replications are conducted by the original studies.
Although the ad refers to replicated studies, independent investigators, those who don't have these replications weren't conducted by independent investigators, a personal or financial conflict of interest in the intervention so it's unclear whether the positive findings reflect biases on the they're testing.

Evaluate the evidence that there are differences in IQ.

buckle your seat belts if you think what we've discussed is controversial.
There are two group differences in IQ: 1) differences between men and women and 2) differences among races.

The issues are emotionally charged and have become deeply entangled in politics, with people on different sides of these debates accusing each other of biases and bad intentions.

Some argue that scientists shouldn't study group differences in IQ.
We need to be as objective as possible when evaluating these issues.
We shouldn't dismiss the ideas that make us feel uneasy out of hand.

It is difficult to evaluate these issues objectively with an open mind to scientific evidence.

Sex differences in IQ and Mental Figure are related to Bachelor's degrees earned by women.

Women have been underrepresented in most of the hard sciences for 40 years, and only a small percentage of those graduating with a degree created a furor.

At an informal meeting of degree in these areas.

He proposed two reasons, one of which was that women prefer raising families over competing in tough jobs.

It was the third reason that 50% really got people going.
He thought that women might have a genetic disadvantage in science and math.
People were appalled.
A prominent woman Biologist from the Massachusetts Institute of Technology walked out of a talk by the President.
Hundreds of Harvard faculty members called for his head within days.

Sex differences in 10% mental abilities were the subject of a lot of controversy.

We'll take a scientifically balanced look at the evidence in this section.

The answers aren't simple.

To show that women's hemispheres are more connected than men's, all fields have to account for women's greater ability to juggle multiple tasks simultaneously.

These brain and behavioral differences are quite small.

The claims that men have slightly higher IQs than women are controversial, to say the least.

Most researchers have found no average sex differences in IQ.

The dispersion of a distribution is looked at in Figure 9.16 Distributions, because average differences don't tell the whole story.

Men and women take IQ tests.

Men don't seem to have the same distribution of women.

We don't know why women with low and high IQs are different, but both genetic and environmental explanations have been proposed.

When it comes to intellectual abilities, men and women are quite similar, but a closer look shows sex differences in a few areas.

Women do better than men on some verbal tasks, like spelling, writing, and pronouncing words.

Chapter 9 estrogen levels peaked in 1988.

Can the results be duplicated in tal abilities within males and females if current levels of sex hormones are found to be associated with men?

When Figure 9.17 Mental Rotation Task is completed, females tend to be better at detecting and recognizing feelings than males.

Men and women in the United States and Mexico speak about 16,000 words a day.

Men tend to do better than women on tasks requiring spatial ability.

Remarkably, this sex difference appears as early as three months of age, rais Men tend to do better than women on tests of mental ing the possibility that it's partly innate.
There is a difference between the shape shown on the left and the one shown on the right.
You might want a different attitude in different countries.

Male rats are faster and more accurate maze runners than female rats.

In Western cultures, men and women have different strategies for finding their way around the world, with men relying on spatial directions alone and women on landmarks.
There is a possibility that this difference isn't entirely biological in non-Western cultures.

One of the largest reported psychological sex differences is in geography.

77 percent of the 5 million children who have participated in the National Geographic Bee have been boys.

Males do better than females on mathematical tasks that involve complicated reasoning.

The difference doesn't emerge until adolescence, perhaps reflecting hormonal changes that occur around puberty.
The difference is magnified at the extreme tails of the bell curve.
For example, in a recent study of students who received scores of 700 or higher on the SAT math section, males outnumbered females by about 4 to 1, a difference that was once as large as 13 to 1 but that appears to have diminished considerably in recent decades.
The low tail of the test has more males than females.

Some sex differences in mental abilities, such as women's higher scores on certain verbal tasks and men's higher scores on spatial and complex math-solving tasks, may be Answer to Figure 9.17: No.

Sex differences in spatial ability have not decreased over time in intelligence and IQ Testing.

Some studies show that excess levels of testosterone, a hormone of which males have more than females, is associated with better spatial ability.

Sex differences in science and math ability can be duplicated.

Sex differences in problem-solving strategies may be the reason for the differences in these abilities later in life.

Men and women are different in how they solve spatial problems.

Over the past three decades, the percentage of women entering the hard sciences has increased.

Some of the underrepresentation of women in the hard sciences may be due to societal factors such as discrimination and societal expectations, rather than women's weaker science skills.

The study of intelligence has found that average IQ scores differ among some races.

Jews have higher IQs than non-Jews in the United States.

The average IQ difference between Caucasians and African Americans has received the most attention.

We will do our best to summarize the complex body of literature that it is.

Some sectors of society have tried to argue that some races are superior to others.

There are a lot of problems with this claim.
First, claims of inherent racial superiority are outside the boundaries of science and can't be answered by data.
The origins of racial differences can only be determined by whether they're genetic, environmental, or both.
The IQ differences between races may be narrowing.
Evidence suggests that the gap between whites and African Americans may have narrowed since for IQ.

This finding shows that the IQ distributions score for different races over points, but they show substantial overlap.

Many African Americans and Hispanics were indicated by the shaded area.

Americans have higher IQs than other people.

We can't use race as a basis for inferring a person's IQ.

There was a bitter dispute between Richard Herrnstein and Charles Murray in 1994.

They maintained that people with high levels of cognitive skills tend to rise to the top of the social ladder.

They make more money, assume more positions of leadership, and enter more powerful occupations because of this.

White 350 Chapter 9 of the IQ gap between races may be genetic.

The two groups of plants are very similar.

Their claims received unprec but one outstrips the other over time because of different press coverage.
The 1960s show how a genetic basis for racial differences could be used to show group differences in IQ.
Jensen's work aroused suspicions of racism.

African Americans are genetically inferior to Caucasians.

He offered an evolutionary explanation for racial differences in IQ during the 1980s and 1990s.

Some researchers have advanced strong arguments for a genetic basis for these differences, but we will soon discover that the majority of evidence shows that these differences are largely or entirely environmental in origin.
The different resources and opportunities available to individuals of different races may be reflected in these differences.

If this example sounds familiar, it's because we introduced a concept very much like it previously in the text.

The plants within each group are different in height.
Plants' tendencies to grow and flourish are reflected in the differences in height.
At this point in the growth cycle, the plants in the two groups are roughly equal in height.
Let's imagine that we provide one group of plants with plenty of water and light, but not the other.

The plants on the left are taller than the plants on the right after we twiddle our thumbs for a few weeks.

The environmental influences resulted in one group growing taller than the other.

We can't explain the difference between the two groups because of watering and light.

The between-group differences are not heritable.
The cumulative effects of such factors as social deprivation and prejudice may produce notable differences in IQ among racial groups, one that's entirely environmental in origin.

One or two individual plants in the shorter group actually grew taller than some plants from the taller group, which is important to note.

The point shows that some plants grow better than others in a group that is less privileged.

We can't use group differences in IQ to infer intelligence because of this point.

The scientific evidence needs to be used for answers to that question.

Some researchers have pointed out that IQ is heritable and that racial differences must be influenced by genetic influences.

Caucasians are heritable between men and women.

It doesn't mean that the difference between these groups has anything to do with their genes.
Some researchers assume that because IQ is heritable within a group such as a race or gender, the differences in IQ must be heritable (Lilienfeld & Waldman, 2000; Nisbett, 1995).
We need to remember that some plants grew taller than others.
The genetic strain of the individual plants within each group caused the differences.

Even though within-group differences were due to genes, the differences between the two groups were due to environmental factors.

The majority of this research is related to analyses of differences between African Americans and Caucasians.

A study was conducted in Germany after World War II to compare the IQ scores of children of African American soldiers and German mothers with those of Caucasian American soldiers and German mothers.

The societal environment was the same in both groups because mothers raised the children.

The two groups of children had the same IQs.

When environment was compared, the different race-related genes appeared to have no bearing on children's IQ.

If racial differences were genetic, it would be expected that European ancestry would give a boost to IQ.

The research shows that African Americans with more ancestors of Caucasian descent have the same IQ as those with few or no such ancestors.
There is no evidence for a genetic explanation of the IQ gap between African Americans and Caucasians.

The effect of cross-racial adoption on IQ was examined in a classic study.

The investigation showed that the IQs of African American children adopted by middle-class Caucasian parents were higher at age seven than the average African American child.
African and Hispanic Americans are more likely to live in poverty than Caucasians and Asian Americans.
The 10-year period may mean that the tendency of a test to predict outcomes is short-lived.

The term test bias has a different meaning for psychologists.

When psychologists use a tape measure to measure height, they don't consider it biased because men get higher average scores than women.

This finding shows that tests of reading are biased against 1996 and that success is better in one group than in another.

A biased test means different things in one group than in the other.

Test bias is represented.

Caucasians have an IQ that is better than Asian Americans.

The average IQ scores for Asian Americans are higher than those of Caucasians.

The answer isn't completely resolved, but it seems to be no.

The correlations between IQ tests and both academic and occupational achievement are about the same for all races.
There may be a few exceptions on specific IQ test items, but they aren't large or frequent to account for the differences across races in IQ.

In the U.S., some races do better in school and have better jobs than others.

Many African and Hispanic Americans are less prepared to compete in higher education and the job market because of these disadvantages.
The finding that IQ tests are equally correlated with reaction time measures across races may not tell the whole story because these measures are unlikely to be affected by social disadvantage.

Stereotype threat creates a prophecy in which people who are anxious about being stereotyped increase their likelihood of doing so.

According to Claude Steele, stereotype threat can affect people's performance on standardized tests.

Intelligence and IQ Testing 353 thought that taking an IQ test would arouse stereotype threat.

Steele believes that this belief can lead some people to display reduced performance.

Steele and his colleagues have shown that stereotype threat can affect African Americans' IQ scores.

When researchers gave African Americans items from an IQ test but told them the items were measuring something other than IQ, they performed better than when the researchers told them the items were measuring IQ.
Stereotype threat manipulation can cause African American participants to become stressed, preoccupied, or overly self- conscious.
Stereotype threat depresses women's scores on measures of mathematical (but not spatial) ability relative to men.

African American students are more likely to perform worse on tests if they are asked to identify their most important personal value, such as their friends, family, or need to express themselves through art.

The meaning of these is not good.

It is possible that focusing on ourselves as individuals rather than as a group renders us less vulnerable to stereotype threat.

The next edition of this textbook will have to sort out whether the results are believable.

Some recent evidence suggests that the size of stereotype threat findings may have been overestimation, perhaps because researchers in this field have been more likely to publish positive than negative findings, which is a widespread bias in scientific research.

Almost all stereotype threat findings come from the tightly controlled world of the psychological laboratory and therefore may be of limited external validity.
The extent to which stereotype threat findings generalize to the real world remains an active area of investigation and debate.

Some researchers and writers in the popular media suggest that racial differences between African Americans and Caucasians on IQ tests are due to stereotype threat and self-fulfilling prophecies.

The effects of stereotype threat aren't large enough to fully account for the gap, although they may account for some of it.

Our discussion leads us to the conclusion that societal differences in resources, opportunities, attitudes, and experiences are likely to be the cause of the racial differences in IQ.

There is no evidence in the research literature that racial differences in IQ can't be changed.
If environmental disadvantages can contribute to IQ differences, they should be eliminated.

Intelligence testing has a history of finding differences between the sexes and certain races.