Question 1

Which of the following best describes a parameter in statistics?

Accepted Answer

A numerical measurement describing some characteristic of a population.

Question 2

A researcher wants to study the effect of a new drug on blood pressure. She randomly assigns patients to either receive the drug or a placebo, and neither the patients nor the staff know who receives which treatment. What is this experimental design called?

Accepted Answer

Double-blind experiment

Question 3

Which sampling method is most likely to introduce bias due to self-selection?

Accepted Answer

Voluntary response sampling

Question 4

A survey asks participants to report their own weight. Which potential pitfall is most relevant in this scenario?

Accepted Answer

Reported vs. measured data

Question 5

Which level of measurement allows meaningful differences between values but does NOT have a natural zero starting point?

Accepted Answer

Interval

Question 6

A researcher divides a city into neighborhoods, randomly selects three neighborhoods, and surveys every household in those neighborhoods. What sampling method is being used?

Accepted Answer

Cluster sampling

Question 7

Which of the following is an example of discrete quantitative data?

Accepted Answer

The number of cars sold at a dealership each day

Question 8

A study collects data on the number of hours students study per week and their exam scores. The data are collected at one point in time. What type of observational study is this?

Accepted Answer

Cross-sectional study

Question 9

Which of the following best illustrates confounding in an experiment?

Accepted Answer

Researchers cannot determine whether the observed effect is due to the treatment or another variable.

Question 10

A researcher selects every 10th person from a list of hospital patients to participate in a study. What sampling method is this?

Accepted Answer

Systematic sampling

Question 11

Which of the following statements about practical significance is TRUE?

Accepted Answer

Practical significance means a result is important enough to justify its practical use.

Question 12

A study finds that a new medication reduces cholesterol by an average of 2 mg/dL with a p-value of 0.01. Which statement best describes the result?

Accepted Answer

The result is statistically significant but may not be practically significant.

Question 13

Which formula represents the probability threshold for statistical significance?

Accepted Answer

$$P \leq 0.05$$

Question 14

A data set contains missing values, and the likelihood of a value being missing is independent of its value or any other data in the set. What is this type of missing data called?

Accepted Answer

Missing Completely at Random (MCAR)

Question 15

Which of the following is an example of ratio level data?

Accepted Answer

Length of time spent in class (minutes)

Question 16

A researcher uses a convenience sample to survey students in the library about their study habits. Which type of error is most likely to occur?

Accepted Answer

Nonrandom sampling error

Question 17

Which of the following best describes the gold standard in experimental design?

Accepted Answer

Randomization paired with treatment and placebo groups

Question 18

A study collects data on the temperature in degrees Fahrenheit at different times of day. What is the level of measurement for this data?

Accepted Answer

Interval

Question 19

Which of the following is a key advantage of replication in experiments?

Accepted Answer

It increases the reliability of observed treatment effects.

Question 20

A researcher wants to compare two teaching methods. She pairs students based on similar test scores and randomly assigns one from each pair to each method. What design is this?

Accepted Answer

Matched pairs design

Chapter 1: Introduction to Statistics – Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard