Argument from Generalization, Sign, Cause & Effect

Assuming the correctness of the data, which of the recognition technologies below would be the least reliable?

A face recognition system at the airport creates one failure to 10,000 accurate recognitions.

How representative (in kind) of the population described was the population that was consulted?

A poll of churchgoers indicates that Americans are very religious.

How representative was the sample?

A questionnaire about male and female bathrooms was given only to members of fraternities on campus.

Was the sample proportional in size to the population about which the sample generalizes?

A sampling of 100 consumers indicates that American consumers want smaller cars.

Failure on a lie detector test could mean the suspect is lying¸ but it could also mean the suspect is just nervous.

Are there alternative causes for the sign?

The falling stock market is signaling a weakening of the economy¸ On other hand¸ job growth is still strong¸ and housing sales are still healthy.

Are there contradictory signs that weaken the connection?

Consumer Confidence Index (issued monthly by the U.S. government since 1967)

Because of the regularity of this sampling over time¸ it's possible to see patterns developing in attitudes.

a "likely voter" opinion poll

Even though this draws from a smaller pool¸ it's probably more accurate than the larger pool of all possible instances¸ because it's based on a strongly predictive behavior (who is likely to do something rather than just who can legally do something).

a soil sample (drawn from a metal probe pushed into the ground)

Even though this sample is very small¸ it is highly predictive because there is not usually a tremendous amount of variation over a contiguous(continuous)area.

Red blotches breaking out all over the body is a very reliable sign of mumps.

How strong is the link between the sign and what it's attributed to?

The Nobel Prize winning ethicist and religious leader testifying on the ethics of cloning has spent her life fighting against the use of technology to manipulate genes and intervene in natural biological processes. As a trial juror listening to this testimony, which question below should probably weigh on you most in considering the merit of this expert's view?

Is the expert unbiased? Does the expert have a vested interest?

How well-established were the analysts who did the sample?

My little sister made a generalization about traffic patterns on our street based on her observations from her lemonade stand.

How well-established an authority was the analyst who made the generalization?

On the way to LaGuardia airport my cab driver told me only rich people live in Manhattan any more.

How big was the sample?

Twenty-seven students filled out the survey at a university of 38¸000 students.

She was tied to the murder by circumstantial evidence¸ but they also had her finger prints at the scene of the crime¸ and confirmed hair samples¸ and a witness who saw her there.

We have quite a number of signs that reinforce the connection.

Choose the items below that the report showed or concluded. Watch the video carefully all the way through with these questions in mind. There are four correct.

a. eye-witness memory can be significantly wrong b. eye-witness memory can be influenced by the investigator e. studies show that almost ½ the time eye-witness testimony convicts an innocent person f. when we try to remember the past we're actually creating details in our memory

Scagegoating and stereotyping are rhetorical techniques that

are sometimes effective in helping shore up a community's sense of self when it feels insecure.

I've just given you some synonyms for warrants. What is NOT used as a rough equivalent to the concept of "warrant" above?

premise

a focus group (a small group of people asked about their opinions in a structured setting by an expert interviewer)

This technique has limited sample size¸ but it provides rich interpretive information elicited by trained experts.

Did the study look for counterexamples? (All it takes is one case of something to disprove a categorical generalization.)

The World Health Organization has proclaimed that polio has been ENTIRELY eliminated from the continent of Africa.

Did the study look for counterexamples?

The scientist disagreed with the truism that all swans are white by producing photographs of black swans.