Stat Ch 1

In the data table​ below, the​ x-values are the weights​ (in pounds) of cars and the​ y-values are the corresponding highway fuel consumption amounts​ (in mi/gal).Weight​ (lb) 4069 3383 4182 3640 3526 Highway Fuel Consumption​ (mi/gal) 27 31 29 29 30

Is there a relationship or an association between the weight of a car and its fuel consumption​ amount?

Determine whether the sampling method described below appears to be sound or is flawed. In a survey of 511 human resource​ professionals, each was asked about the importance of the education of a job applicant. The survey subjects were randomly selected by pollsters from a reputable market research firm.

It appears to be sound because the data are not biased in any way.

Determine whether the sampling method described below appears to be sound or is flawed. In a survey of 517 ​subjects, each was asked how often he or she watched TV. The survey subjects were internet users who responded to a question that was posted on a news website.

It is flawed because it is a voluntary response sample.

The IQ score and brain volume are listed for each of five different subjects. Refer to the table of measurements below. Given that the data are matched and considering the units of the​ data, does it make sense to use the difference between each IQ score and brain volume that is in the same​ column? Why or why​ not?

No, it does not make sense to use the difference between each IQ score and brain volume in the same​ column, because IQ scores and brain volumes use different units of measurement.

Refer to the sample of body temperatures​ (degrees Fahrenheit) in the table below. Given these​ temperatures, what issue can be addressed by conducting a statistical analysis of the​ data?

The data can be used to address the issue of whether there is a correlation between body temperatures at 8 AM and at 12 AM.

An article noted that chocolate is rich in flavonoids. The article reports that​ "regular consumption of foods rich in flavonoids may reduce the risk of coronary heart​ disease." The study received funding from a candy company and a chocolate manufacturers association. Identify and explain at least one source of bias in the study described. Then suggest how the bias might have been avoided.

The researchers may have been more inclined to provide favorable results because funding was provided by a party with a definite interest. The bias could have been avoided if the researchers were not paid by the candy company and the chocolate manufacturers.

A​ magazine, which does not accept free products or advertising from​ anyone, prints a review of new cars. Are there sources of bias in this​ situation?

There do not appear to be any sources of bias.

Determine whether the source given below has the potential to create a bias in a statistical study. A certain medical organization tends to oppose the use of meat and dairy products in our​ diets, and that organization has received hundreds of thousands of dollars in funding from an animal rights foundation.

There does appear to be a potential to create a bias. There is an incentive to produce results that are in line with the​ organization's creed and that of its funders

Determine whether the source given below has the potential to create a bias in a statistical study. Washington University obtained word counts from the most popular novels of the past five years.

There does not appear to be a potential to create a bias. The organization would not gain from putting a spin on the results.

A newspaper posted this question on its​ website: "How often do you seek medical information​ online?" Of 1072 Internet users who chose to​ respond, 38% of them responded with​ "frequently." What term is used to describe this type of survey in which the people surveyed consist of those who decided to​ respond? What is wrong with this type of sampling​ method?

What term is used to describe this type of​ survey? Select all that apply. The respondents are a​ self-selected sample. The respondents are a voluntary response sample.

In the data table​ below, the​ x-values are the weights​ (in pounds) of cars and the​ y-values are the corresponding highway fuel consumption amounts​ (in mi/gal). Weight​ (lb) 4074 3321 4113 3633 3584 Highway Fuel Consumption​ (mi/gal) 25 31 29 28 30

Yes, because​ consumers, in​ general, would prefer to buy a car with a higher level of fuel efficiency. In this​ case, the source of the data would be suspect with a potential for bias.

Refer to the table of body temperatures​ (degrees Fahrenheit). Is there some meaningful way in which each body temperature recorded at 8 AM is matched with the 12 AM​ temperature? Subject 1 2 3 4 5 8 AM 97.0 98.5 97.6 97.7 98.7 12 AM 97.6 97.8 98.0 98.4 98.4

Yes. Each column of 8 AM and 12 AM temperatures is recorded from the same​ subject, so each pair is matched.

In the data table​ below, the​ x-values are the weights​ (in pounds) of cars and the​ y-values are the corresponding highway fuel consumption amounts​ (in mi/gal). Weight​ (lb) 4013 3396 4140 3608 3515 Highway Fuel Consumption​ (mi/gal) 26 32 29 28 30

​Yes, because​ consumers, in​ general, would prefer to buy a car with a higher level of fuel efficiency. In this​ case, the source of the data would be suspect with a potential for bias.