Question 1

The First National Bank mailed out a survey to all 3,456 savings account customers. A total of 568 surveys were returned. Values computed from the returned surveys would constitute parameters since all 568 customers were surveyed.

Accepted Answer

Values computed from the returned surveys would constitute statistics, not parameters, because they are derived from a sample (568 respondents) of the entire population (3,456 customers), not the entire population itself.

Question 2

When a company scans the bar codes on its products in an effort to count the number of products that remain in inventory, the company is collecting data through experimentation.

Accepted Answer

Scanning bar codes to count inventory is an example of observational data collection, not experimentation, as it involves observing and recording existing conditions without manipulating any variables.

Question 3

Data collected on the Internet can generally be considered accurate since the data must go through a screening process before they can be placed on the Internet.

Accepted Answer

There is no universal screening process for data published on the Internet, meaning anyone can post information, which may not always be accurate or reliable.

Question 4

A pharmaceutical company conducts a study where 50 patients are given a drug. They find that 10 percent of patients experience nausea as a side effect. This 10 percent is an example of a parameter.

Accepted Answer

This 10 percent is an example of a statistic because it is a measure derived from a sample (the 50 patients) rather than the entire population.

Question 5

When the production manager selects a sample of items that have been produced on her production line and computes the proportion of those items that are defective, the proportion is referred to as a statistic.

Accepted Answer

The proportion of defective items computed from a sample is a statistic because it is a numerical measure that describes a characteristic of a sample.

Question 6

When a survey is done you can always assume that non-respondents would have answered the same way as those who did respond.

Accepted Answer

Non-respondents may have different opinions or characteristics than those who responded, potentially leading to nonresponse bias in the survey results.

Question 7

When the marketing manager for a large company surveys a portion of the total customers of his company, he is using a sample from the population.

Accepted Answer

A sample refers to a subset of individuals, items, or data taken from a larger population for the purpose of analysis. In this case, the portion of total customers surveyed by the marketing manager represents a sample from the broader population of all the company's customers.

Question 8

When people fail to respond to a survey, the data collection process may suffer from nonresponse bias.

Accepted Answer

Nonresponse bias occurs when individuals who do not participate in a survey differ significantly from those who do, potentially skewing the results and making them unrepresentative of the entire population.

Question 9

It is possible for an interviewer to interject bias into the data collection project by the way he or she asks the questions.

Accepted Answer

The way questions are phrased or the tone used by an interviewer can influence respondents' answers, introducing bias into the data collection process.

Question 10

A sample is selected from a population in cases where selecting data from the entire population is either very difficult or very expensive.

Accepted Answer

Sampling is often used because it is more practical, cost-effective, and less time-consuming than collecting data from an entire population.

Question 11

When university newspaper reporters take a poll of students by standing outside of the nearest pub to survey students about the university offering upgraded food options, the sampling method used is called a random sample.

Accepted Answer

This is not a random sample because it does not give all students an equal chance of being selected. It is a convenience sample, as the reporters are choosing participants based on their easy availability and proximity, not through a random selection process.

Question 12

A parameter is the boundary on the population of interest.

Accepted Answer

A parameter is a numerical characteristic of a population, not the boundary on the population of interest.

Question 13

If an analyst computes statistics from a sample, the sample is by definition a statistical sample.

Accepted Answer

The answer of If an analyst computes statistics from a...

Question 14

Recently, an analyst in a company's marketing department surveyed customers regarding how often they buy a particular product. One customer indicated that she purchased the product 17 times in the last six months, but the analyst recorded the response as 71 times. This is an example of observer bias.

Accepted Answer

This is an example of a data entry error or recording error, not observer bias. Observer bias occurs when the researcher's expectations or preferences influence the recording of data or interpretation of results, not simple mistakes in data transcription.

Question 15

Selection bias occurs when the respondent decides which of the questions on the survey to answer.

Accepted Answer

Selection bias refers to a distortion in a statistical analysis, resulting from the method of collecting samples. It occurs when the sample obtained is not representative of the population intended to be analyzed, not from respondents choosing which questions to answer on a survey.

Question 16

Population parameters are descriptive numerical measures, such as an average, that describe the entire population.

Accepted Answer

Population parameters are indeed numerical measures that describe characteristics of an entire population, such as the mean (average), median, mode, variance, and standard deviation.

Question 17

Statistics are measures computed from the entire population of data.

Accepted Answer

Statistics are measures computed from a sample of data, whereas parameters are measures computed from the entire population.

Question 18

It is possible for a nonstatistical sample to yield statistics that have values closer to the corresponding parameter than will a statistical sample.

Accepted Answer

A nonstatistical sample, if carefully selected with expert judgment, can yield statistics that closely match the population parameters, especially in cases where the sample is highly representative of the population. However, this does not guarantee the reliability and generalizability of the results compared to a properly selected statistical sample.

Question 19

A census is an enumeration of the entire sample of items selected from the population of interest.

Accepted Answer

A census is an enumeration of the entire population of interest, not just a sample.

Question 20

When the United States conducts a census that counts all people in the country, this is an example of using a sample.

Accepted Answer

A census involves counting every individual in the entire population, not just a sample.

Quiz 1: The Where, Why, and How of Data Collection