Question 1

Which of the following best describes a parameter in statistics?

Accepted Answer

A numerical summary of a population.

Question 2

A pharmaceutical company wants to estimate the average time it takes for a new drug to relieve headache pain. They test the drug on 200 randomly selected patients and calculate the mean relief time. What is the sample in this scenario?

Accepted Answer

The 200 patients who were given the drug.

Question 3

Which of the following variables is quantitative and continuous?

Accepted Answer

The height of a plant measured in centimeters.

Question 4

A researcher records the blood types (A, B, AB, O) of 1000 newborns in a hospital. What is the level of measurement for this variable?

Accepted Answer

Nominal

Question 5

Which of the following best describes an observational study?

Accepted Answer

A study in which the researcher observes individuals and measures variables of interest without influencing the responses.

Question 6

A nutritionist wants to know if a new diet plan affects cholesterol levels. She randomly assigns 100 participants to either the new diet or their usual diet and measures their cholesterol after 6 months. What type of study is this?

Accepted Answer

Designed experiment

Question 7

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

Accepted Answer

The number of cars passing through a toll booth in an hour.

Question 8

A survey asks respondents to rate their satisfaction with a service as 'very dissatisfied', 'dissatisfied', 'neutral', 'satisfied', or 'very satisfied'. What is the level of measurement for this variable?

Accepted Answer

Ordinal

Question 9

Which of the following statements about statistics and parameters is correct?

Accepted Answer

A statistic describes a sample, while a parameter describes a population.

Question 10

A researcher wants to estimate the average number of hours college students sleep per night. She surveys 150 students at her university. Which of the following is the population?

Accepted Answer

All college students.

Question 11

Which sampling method is used when a researcher divides a population into groups based on a characteristic (such as age) and then randomly selects some groups to survey all members within those groups?

Accepted Answer

Cluster sampling

Question 12

A study finds that the mean cholesterol level of a sample of 500 adults is 190 mg/dL. Which of the following is a statistic?

Accepted Answer

The mean cholesterol level of the 500 adults in the sample.

Question 13

Which of the following best describes a qualitative variable?

Accepted Answer

A variable that describes an attribute or category.

Question 14

A hospital records the number of patients admitted each day for a month. What type of variable is 'number of patients admitted'?

Accepted Answer

Quantitative and discrete

Question 15

Which of the following is an example of data measured at the interval level?

Accepted Answer

The temperature in degrees Celsius.

Question 16

A researcher wants to study the effect of exercise on blood pressure. She randomly assigns participants to either an exercise group or a control group and measures their blood pressure after 8 weeks. What is the explanatory variable?

Accepted Answer

Group assignment (exercise or control).

Question 17

Which of the following best describes a cross-sectional study?

Accepted Answer

A study that collects information about individuals at a specific point in time.

Question 18

A teacher wants to select a sample of students from her class of 30. She writes each student's name on a slip of paper, puts them in a hat, and draws 5 names. What type of sampling is this?

Accepted Answer

Simple random sampling

Question 19

Which of the following is a correct statement about the difference between a designed experiment and an observational study?

Accepted Answer

A designed experiment allows the researcher to claim causation, while an observational study does not.

Question 20

A study finds that the average test score of a sample of 50 students is 78. Which of the following is a parameter?

Accepted Answer

The average test score of all students in the school.

Foundations of Statistics: Key Concepts, Variables, Sampling, and Study Design

Guida di studio - Domande di pratica

Study guide - Flashcard