Question 1

TABLE 1-1
The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a videocassette recorder made by the company over the past 12 months are satisfied with their products.
-Referring to Table 1-1, the possible responses to the question "In which year were you born?" are values from a

Accepted Answer

The year of birth is a discrete numerical random variable because it takes on distinct, separate values (years) and is countable.

Question 2

Referring to Table 1-1, the possible responses to the question "How much time do you use the videocassette recorder every week on the average?" result in

Accepted Answer

The possible responses to the question "How much time do you use the videocassette recorder every week on the average?" result in a ratio scale variable because the responses are numerical and have a fixed interval between them (e.g. 0-2 hours, 2-4 hours, etc.) and there is an absolute zero point (0 hours), which is a meaningful value.

Question 3

A summary measure that is computed to describe a characteristic of an entire population is called

Accepted Answer

A parameter is a summary measure that describes a characteristic of an entire population. Statistics are summary measures computed from a sample, while the scientific method is a systematic approach used to generate knowledge through observation and experimentation. A census involves collecting data from the entire population, which may not always be feasible or necessary.

Question 4

Researchers are concerned that the weight of the average American school child is increasing implying, among other things, that children's clothing should be manufactured and marketed in larger sizes. If X is the weight of school children sampled in a nationwide study, then X is an example of

Accepted Answer

The weight of school children sampled is a continuous random variable as it can technically take on any value within a certain range (even if we only measure to the nearest pound). It is not discrete (which would be something that can only take on specific values such as the number of siblings a child has) or categorical (which would be something like hair color where the values are distinct categories). It is also not a parameter as a parameter is a summary measure of a population, not an individual value from a sample.

Question 5

TABLE 1-1
The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a videocassette recorder made by the company over the past 12 months are satisfied with their products.
-Referring to Table 1-1, the possible responses to the question "In which year were you born?" result in

Accepted Answer

The answer of TABLE 1-1
The manager of the customer service...

Question 6

TABLE 1-1
The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a videocassette recorder made by the company over the past 12 months are satisfied with their products.
-Referring to Table 1-1, the possible responses to the question "How many people are there in your household?" result in

Accepted Answer

The question "How many people are there in your household?" results in a ratio scale variable because it has a true zero point and allows for the comparison of absolute magnitudes.

Question 7

A study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the beaches from environmental disasters. Twenty-five hundred Florida residents were surveyed. What type of data collection procedure was most likely used to collect the data for this study?

Accepted Answer

A random sample was likely used to collect the data because it is a survey of Florida residents and it would be difficult to conduct a designed experiment or obtain observational data in this situation. Additionally, a published source would not provide information specific to the study's research question.

Question 8

TABLE 1-1
The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a videocassette recorder made by the company over the past 12 months are satisfied with their products.
-Referring to Table 1-1, the possible responses to the question "How would you rate the quality of your purchase experience with 1 = excellent, 2 = good, 3 = decent, 4 = poor, 5 = terrible?" result in

Accepted Answer

The responses given are ranked from 1 to 5 in terms of quality, indicating an ordinal scale variable. While the values assigned to each response may not have a mathematically equal distance between them, they do have an inherent order.

Question 9

Most analysts focus on the cost of tuition as the way to measure the cost of a college education. But incidentals, such as textbook costs, are rarely considered. A researcher at Drummand University wishes to estimate the textbook costs of first-year students at Drummand. To do so, she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $300 per semester. Identify the variable of interest to the researcher.

Accepted Answer

The variable of interest to the researcher is the textbook cost of first-year Drummand University students. This is because the researcher is specifically trying to estimate the textbook costs of first-year students at Drummand. The other answer choices are not as relevant to the researcher's goal.

Question 10

The universe or "totality of items or things" under consideration is called

Accepted Answer

The universe or "totality of items or things" is typically referred to as a population in statistics.

Question 11

The portion of the universe that has been selected for analysis is called

Accepted Answer

The portion of the universe selected for analysis is called a sample, which is a subset of the population or universe being studied. Parameters are numerical summaries of the entire population, while statistics are numerical summaries of a sample. A frame is a list of units from which a sample is selected.

Question 12

The personnel director at a large company studied the eating habits of the company's employees. The director noted whether employees brought their own lunches to work, ate at the company cafeteria, or went out to lunch. The goal of the study was to improve the food service at the company cafeteria. This type of data collection would best be considered as

Accepted Answer

This type of data collection is an observational study since the director is simply observing and recording the eating habits of the employees without manipulating any variables. There is no randomization or manipulation of variables, so it cannot be a designed experiment. It also does not involve selecting a specific number of employees for each group, so it is not a quota sample.

Question 13

The chancellor of a major university was concerned about alcohol abuse on her campus and wanted to find out the proportion of students at her university who visited campus bars on the weekend before the final exam week. Her assistant took a random sample of 250 students and computed the portion of students in the sample who visited campus bars on the weekend before the final exam. The portion of all students at her university who visited campus bars on the weekend before the final exam week is an example of

Accepted Answer

The portion of all students at the university who visited campus bars on the weekend before the final exam week is a characteristic of the entire population of students at the university, and therefore, it is a parameter.

Question 14

Jared was working on a project to look at global warming and accessed an Internet site where he captured average global surface temperatures from 1866. Which of the four methods of data collection was he using?

Accepted Answer

Jared accessed an Internet site with published data, which falls under the method of data collection through published sources.

Question 15

TABLE 1-1
The manager of the customer service division of a major consumer electronics company is interested in determining whether the customers who have purchased a videocassette recorder made by the company over the past 12 months are satisfied with their products.
-Referring to Table 1-1, the possible responses to the question "How would you rate the quality of your purchase experience with 1 = excellent, 2 = good, 3 = decent, 4 = poor, 5 = terrible?" are values from a

Accepted Answer

The responses are values from a categorical random variable since they represent different categories rather than numerical values that can be measured on a continuous scale.

Question 16

Tim was planning for a meeting with his boss to discuss a raise in his annual salary. In preparation, he wanted to use the Consumer Price Index to determine the percentage increase in his real (inflation-adjusted) salary over the last three years. Which of the 4 methods of data collection was involved when he used the Consumer Price Index?

Accepted Answer

The Consumer Price Index is a published source that provides information on the average change in prices paid by consumers for goods and services over time. Therefore, the method of data collection involved in using the Consumer Price Index is published sources.

Question 17

The collection and summarization of the socioeconomic and physical characteristics of the employees of a particular firm is an example of

Accepted Answer

Descriptive statistics involves the collection, organization, and summarization of data, which includes the socioeconomic and physical characteristics of employees in this example. A statistic is a numerical summary of a sample, while a parameter is a numerical summary of a population. Inferential statistics involves making inferences or predictions about a population based on a sample. None of these apply to the given example as it only involves the collection and summarization of data.

Question 18

A study is under way in Yosemite National Forest to determine the adult height of American pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American pines. The study involves collecting heights from 250 randomly selected adult American pine trees and analyzing the results. Identify the variable of interest in the study.

Accepted Answer

The variable of interest in the study is the height of an American pine tree in Yosemite National Forest, as the study aims to determine what factors aid a tree in reaching heights greater than 60 feet tall. The other options (A, B, and C) are not directly related to the study objective.

Question 19

Referring to Table 1-1, the possible responses to the question "Are you happy, indifferent, or unhappy with the performance per dollar spent on the videocassette recorder?" are values from a

Accepted Answer

The possible responses are categorical in nature, as they are not numerical values and represent different categories of satisfaction levels. Therefore, the best choice is D, a categorical random variable.

Question 20

To monitor campus security, the campus police office is taking a survey of the number of students in a parking lot each 30 minutes of a 24-hour period with the goal of determining when patrols of the lot would serve the most students. If X is the number of students in the lot each period of time, then X is an example of

Accepted Answer

X is a count of the number of students, which is a discrete variable because it can only take on whole number values. It is also a random variable because its value is subject to chance variability. It is not a categorical variable because it is not a label or a category, and it is not a statistic because it is not a summary of a sample of data.

Quiz 1: Introduction and Data Collection