Question 1

Which of the following best describes the main goal of inferential statistics?

Accepted Answer

To use data from a sample to make generalizations about a population and measure the reliability of those generalizations.

Question 2

A researcher wants to study the effect of a new teaching method on student performance. She randomly assigns 100 students to two groups: one group receives the new method, and the other receives the traditional method. At the end of the semester, she compares their test scores. What type of study is this?

Accepted Answer

Designed experiment

Question 3

Which of the following variables is measured at the ratio level of measurement?

Accepted Answer

Number of days a student studied last week

Question 4

A hospital administrator wants to estimate the average waiting time in the emergency room. She divides patients into three groups based on severity (minor, moderate, severe) and randomly selects 20 patients from each group. What sampling method is being used?

Accepted Answer

Stratified sampling

Question 5

Which of the following is an example of a continuous variable?

Accepted Answer

Distance a car travels on a full tank of gas

Question 6

A survey is conducted by asking every 10th person leaving a grocery store about their shopping experience. If the first person is randomly selected from the first 10, which sampling method is this?

Accepted Answer

Systematic sampling

Question 7

In a study, researchers want to determine if a new drug reduces blood pressure. They pair participants by age and gender, then randomly assign one in each pair to receive the drug and the other to receive a placebo. What experimental design is this?

Accepted Answer

Matched-pairs design

Question 8

Which of the following is a source of nonresponse bias in a survey?

Accepted Answer

Some selected individuals do not respond, and their opinions differ from those who do respond

Question 9

A researcher wants to study the average household income in a city. She randomly selects 10 city blocks and surveys every household within those blocks. What type of sampling is this?

Accepted Answer

Cluster sampling

Question 10

Which of the following best describes a lurking variable?

Accepted Answer

A variable not considered in a study that affects the value of the response variable

Question 11

Suppose a sample of 100 students is selected from a university of 10,000 students, and the average GPA of the sample is calculated. Which of the following terms best describes the average GPA of the sample?

Accepted Answer

Statistic

Question 12

A researcher collects data on the number of books read by each student in a class during the semester. What type of variable is 'number of books read'?

Accepted Answer

Quantitative, discrete

Question 13

Which of the following is an example of response bias in a survey?

Accepted Answer

Respondents give answers they think are socially acceptable rather than their true opinions

Question 14

In a randomized block design, what is the main purpose of blocking?

Accepted Answer

To group similar experimental units together to reduce variability due to known factors

Question 15

A study collects data on the favorite color of each child in a kindergarten class. What is the level of measurement for this variable?

Accepted Answer

Nominal

Question 16

A pharmaceutical company conducts a double-blind, placebo-controlled experiment to test a new medication. Which of the following statements is true about this design?

Accepted Answer

Neither the subjects nor the researchers know which treatment each subject is receiving.

Question 17

A sample is said to be biased if:

Accepted Answer

It is not representative of the population.

Question 18

Which of the following best describes a case-control study?

Accepted Answer

A retrospective study that matches individuals with a certain characteristic to those without it

Question 19

Suppose you want to select a simple random sample of 5 students from a class of 30. Which of the following procedures would ensure a simple random sample?

Accepted Answer

Assign each student a number from 1 to 30 and use a random number generator to select 5 unique numbers.

Question 20

A researcher is interested in the effect of fertilizer on plant growth. She divides 60 plants into two groups based on plant variety, then randomly assigns treatments within each group. What experimental design is this?

Accepted Answer

Randomized block design

Chapter 1: Data Collection – Foundations of Statistical Study

Guida di studio - Domande di pratica

Study guide - Flashcard