Statistics (science)

Question 1

What is the definition of statistics?

Answer 1

Statistics is the science of collecting, analyzing, interpreting, presenting, and organizing data.

Question 2

True or False: Descriptive statistics summarize data without making conclusions about the population.

Answer 2

True

Question 3

What is the purpose of inferential statistics?

Answer 3

Inferential statistics allow us to make predictions or inferences about a population based on a sample of data.

Question 4

Fill in the blank: The measure of the center of a dataset is called the _______.

Answer 4

mean

Question 5

What does the standard deviation measure?

Answer 5

The standard deviation measures the amount of variation or dispersion in a set of values.

Question 6

Multiple choice: Which of the following is a measure of central tendency? A) Variance B) Mode C) Standard deviation

Answer 6

B) Mode

Question 7

What is a population in statistics?

Answer 7

A population is the entire group of individuals or instances about whom we hope to learn.

Question 8

True or False: A sample is a subset of a population.

Answer 8

True

Question 9

What is the difference between qualitative and quantitative data?

Answer 9

Qualitative data describes characteristics or qualities, while quantitative data represents numerical values.

Question 10

Fill in the blank: The _______ is the value that appears most frequently in a data set.

Answer 10

mode

Question 11

What is the range of a data set?

Answer 11

The range is the difference between the highest and lowest values in the data set.

Question 12

Multiple choice: Which of the following is not a type of bias? A) Selection bias B) Confirmation bias C) Normal bias

Answer 12

C) Normal bias

Question 13

What is a hypothesis in statistics?

Answer 13

A hypothesis is a testable statement about the relationship between two or more variables.

Question 14

True or False: A p-value less than 0.05 typically indicates statistical significance.

Answer 14

True

Question 15

Fill in the blank: In a normal distribution, approximately _______% of the data falls within one standard deviation of the mean.

Answer 15

68

Question 16

What is a confidence interval?

Answer 16

A confidence interval is a range of values that is likely to contain the population parameter with a certain level of confidence.

Question 17

Multiple choice: What does a correlation coefficient of -1 indicate? A) No correlation B) Positive correlation C) Perfect negative correlation

Answer 17

C) Perfect negative correlation

Question 18

What is the purpose of a regression analysis?

Answer 18

Regression analysis estimates the relationships among variables.

Question 19

True or False: Outliers are data points that differ significantly from other observations.

Answer 19

True

Question 20

Fill in the blank: The _______ is the middle value when the data is ordered from least to greatest.

Answer 20

median

Question 21

What is the null hypothesis?

Answer 21

The null hypothesis is a statement that there is no effect or no difference, and it is what we seek to test against.

Question 22

Multiple choice: Which of the following is a type of data visualization? A) Histogram B) Pie chart C) Both A and B

Answer 22

C) Both A and B

Question 23

What does a box plot represent?

Answer 23

A box plot represents the distribution of a dataset based on a five-number summary: minimum, first quartile, median, third quartile, and maximum.

Question 24

True or False: The mean is always greater than the median in a skewed distribution.

Answer 24

False

Question 25

Fill in the blank: A _______ variable is one that can take on a range of values.

Answer 25

continuous

Question 26

What is the significance of the Central Limit Theorem?

Answer 26

The Central Limit Theorem states that the distribution of sample means approaches a normal distribution as the sample size increases, regardless of the population's distribution.

Question 27

Multiple choice: Which test is used to compare the means of two groups? A) T-test B) ANOVA C) Chi-square test

Answer 27

A) T-test

Question 28

What is skewness in statistics?

Answer 28

Skewness measures the asymmetry of the probability distribution of a real-valued random variable.

Question 29

True or False: A larger sample size generally leads to more reliable results.

Answer 29

True

Question 30

Fill in the blank: The _______ is a statistical method used to determine if there is a significant association between two categorical variables.

Answer 30

Chi-square test

Question 31

What does the term 'type I error' refer to?

Answer 31

A type I error occurs when the null hypothesis is incorrectly rejected when it is actually true.

Question 32

What is the purpose of a scatter plot?

Answer 32

A scatter plot is used to determine the relationship between two quantitative variables.

Question 33

Multiple choice: What is the significance level (alpha) in hypothesis testing? A) The probability of rejecting the null hypothesis when it is true B) The probability of accepting the null hypothesis when it is false C) The probability of a type II error

Answer 33

A) The probability of rejecting the null hypothesis when it is true

Question 34

What is the difference between a one-tailed and a two-tailed test?

Answer 34

A one-tailed test looks for an effect in one direction, while a two-tailed test looks for effects in both directions.