Psych Module 2 & 4

You are a school psychologist who administers the Wechsler Intelligence Scale for Children (WISC) to all sixth graders before they enter into junior high. You notice that the intelligence scores have a smaller standard deviation than when you administer the WISC to children in your consulting practice. Why?

The community in your consulting practice is more diverse than the school.

Robyn is considering leaving college to pursue a career in software development. She is impressed by an article, which shows that some of the most successful entrepreneurs in this field did not complete college. Robyn is:

generalizing from a biased sample

Random samples provide ___________ estimates of population averages if the samples have small ___________.

good; standard deviations

Researchers use _____ to determine whether a study's outcome is due to chance or not, and whether the outcome can be generalized to a larger population.

inferential statistics

After carrying out the appropriate statistical calculations of their data, the researchers concluded that the probability of obtaining the results, if random factors alone were operating, was less than 1 chance out of a 100. The researchers used _____, and can conclude that the results are _____.

inferential statistics; statistically significant

If the results of a study are deemed significant, this means that the observed difference:

is probably not due to chance variation between the samples.

Differences between two samples are MOST likely to be statistically significant if the samples are:

large and the standard deviations of the samples are small.

Professor Ramirez recorded men's and women's scores on a laboratory test of aggression, and found a gender difference. He is not likely to report his findings significant unless the odds of the results occurring by chance are:

less than 5%

In terms of variation in the data, averages that are derived from scores with ____ variability are more reliable than averages based on scores with ____ variability.

low; high

A few atypical scores can distort this measure of central tendency.

mean

One person in a group of 10 people is 10 times older than any of the other members. With respect to age, it is most likely that the majority of group members are younger than the group's:

mean

The ____________ can be particularly biased or misleading when there are a few ____________ scores.

mean; extreme

Ahmed has five sisters who are 3, 3, 5, 9, and 10 years of age. The number 5 represents the __________ of his sisters' ages.

median

The ____________ is the one measure of central tendency that is not affected by extremely high or low numbers.

median

The latest incomes have just been released for people living in your community. The average annual income is listed as $75,000 per person; however, you find this strange because the majority of people in the community work at the local factory making under $50,000 a year. Upon further research at the town hall, you discover that the average annual income is actually $39,000, by using what measure of central tendency?

median

The ____________ is a measure of ____________.

median; central tendency

The ____________ is a simple measure of central tendency, which indicates the score or scores that occur most frequently.

mode

The number 7 is the ___________ of the following set of numbers: 1, 1, 2, 2, 3, 3, 4, 7, 7, 7, 8, 9.

mode

Seeing faces in a puddle of water, perceiving that answers on a true-false exam have an order, or hearing hidden messages in music are examples of our tendency to perceive ____, which is an error in thinking.

order in random events

One way to not be misled by "off-the-top-of-the-head" estimates is to make sure to use basic _____________ in everyday reasoning.

statistical principles

What is the median of the following set of numbers: 1, 1, 2, 2, 3, 3, 4, 7, 7, 7, 9?

3

What is the mean of the following set of numbers: 1, 1, 2, 2, 3, 3, 4, 7, 7, 7, 9?

4.2

Janelle has five brothers who are 4, 6, 6, 9, and 15 years of age. What is the mean age of Janelle's brothers?

8

Each Question should start with "1" or be successively numbered.

Each successive choice should start with the next letter and period.

You are reading the latest issue of the Journal of Neuropsychology, and the article on a new neurocognitive test for Alzheimer's disease catches your attention. You are excited because it states that the new test is quite successful and has statistical significance. The article further states that the new test should be given to all Alzheimer patients. You look back at the beginning of the article and find that the new test was given to 35 research participants. What do you conclude?

Generalizations based on a small number of cases are unreliable.

Francine is thinking about placing a bet in a fantasy football league that her brothers have formed. Given what you know about averages and variability, which of the following would be the surest team for her to bet on given the information provided?

a team that scored between 14 and 17 in its first 10 games of the season

Tonya was astonished when she flipped a coin 10 times and it came up heads each time. She believed that this was her lucky day and spent $10 on lottery tickets. Tonya's belief is an example of our tendency to perceive ____, which is an error in thinking.

order in random events

One important point to remember is that just because a difference between two treatment groups is found to be statistically significant, does not mean that the difference has:

practical significance

To say that the difference between sample averages is statistically significant means that the difference is:

probably NOT due to chance variation.

Even in random data we often find order, because random sequences often don't look _____.

random

Because a few extreme scores can create a deceptively large estimate of variation, the _________ offers only a crude estimate of the variation in a data set.

range

The ________________ is a computed measure of how much the scores vary around the mean score.

standard deviation

The ________________ is a measure of ________________.

standard deviation; variation

When trying to interpret a bar graph, do not be fooled. Make sure to check the _____________ and note their _____________.

scale labels; range

People see a face on the Moon, hear Satanic messages in music, and perceive the Virgin Mary's image on a grilled cheese sandwich. This is an example of our tendency to:

see patterns because we want to make sense of the world.

Jack was listening to an old Beatles album and thought he heard a hidden message proclaiming that Paul McCartney was dead. This is an example of our tendency to:

see patterns because we want to make sense out the world.

You are trying to decide between two schools for your 8-year-old daughter to attend. The Einstein School brags that the average IQ of its students is 125, with a standard deviation of 5.3. The Marie Curie School reports that the average IQ of its students is 125, with a standard deviation of 15.6. If you are most interested in finding a school that has children with diverse abilities, which school would you choose for your daughter?

the Marie Curie School

Your least favorite fast food restaurant has recently placed a large advertisement in several national newspapers. It claims that people who eat at this restaurant lose more weight than do people eating at a competing restaurant. The advertisement includes a simple bar graph displaying this information. What should you look for in the bar graph to make sure their claims are accurate?

the scale labels and their range

When we are generalizing from a sample, we must keep in mind all of the following EXCEPT:

unrepresentative samples are better than biased samples.

When trying to interpret measures of central tendency, it is also important to know something about the ____________ in the data set.

variation