Statistics

Question 1

Which measure of central tendency represents the most frequently occurring value in a dataset?

A) Mean
B) Median
C) Mode
D) Range

Answer 1

C) Mode

Question 2

Which measure of central tendency is best used when the dataset contains outliers?

A) Mean
B) Median
C) Mode
D) Range

Answer 2

B) Median

Question 3

• difference between highest and lowest observation in a data

Answer 3

Range

Question 4

True or False

The median is less affected by outliers compared to the mean, making it a better measure of central tendency when outliers are present

Answer 4

True

Question 5

Which measure of variability indicates the average distance of each data point from the mean?

A) Range
B) Interquartile range
C) Variance
D) Standard deviation

Answer 5

D) Standard deviation

Question 6

used to measure how far the data values are dispersed from the mean

Answer 6

variance

Question 7

True or False

Standard deviation measures the average distance of each data point from the mean, providing insight into the spread of the data.

Answer 7

true

Question 8

True or False

In a positively skewed distribution, the mean is lower than the median, which is lower than the mode, due to the tail on the right side.

Answer 8

False

In a positively skewed distribution, the mean is greater than the median, which is greater than the mode, due to the tail on the right side

Question 9

Which of the following is a measure of the central location of a dataset?

A) Standard deviation
B) Variance
C) Median
D) Interquartile range

Answer 9

C) Median

Question 10

Which measure of spread is defined as the difference between the first quartile and the third quartile?
A) Range
B) Standard deviation
C) Variance
D) Interquartile range

Answer 10

D) Interquartile range

Question 11

In hypothesis testing, what is the p-value?

A) The probability of accepting the null hypothesis
B) The probability of rejecting the null hypothesis when it is true C) The probability of observing the test results under the null hypothesis
D) The level of significance

Answer 11

C) The probability of observing the test results under the null hypothesis

Question 12

Which of the following is a Type I error?

A) Rejecting the null hypothesis when it is true
B) Accepting the null hypothesis when it is false
C) Failing to reject the null hypothesis when it is false
D) Failing to accept the null hypothesis when it is true

Answer 12

A) Rejecting the null hypothesis when it is true

Question 13

If you are going to describe the findings of a survey about what annual income is for the people of Makati City, in which you have both extremely wealthy and extremely poor people, which two measures would you use?

A) Mean and Mode
B) Mean and Range
C) Mean and Standard Deviation
D) Mode and Standard Deviation

Answer 13

C) Mean and Standard Deviation

Question 14

In a confidence interval, what does the margin of error represent?

A) The range of values within which the population parameter lies B) The standard deviation of the sample
C) The maximum error allowed in the estimate
D) The sample mean

Answer 14

C) The maximum error allowed in the estimate

Question 15

indicates the range within which we expect the true population parameter to lie

Answer 15

margin of error

Question 16

What does a confidence level of 95% mean?

A) There is a 95% probability that the sample mean is within the confidence interval
B) 95% of the population data lies within the confidence interval C) 95% of the time, the true population parameter lies within the confidence interval
D) There is a 5% chance that the sample mean lies outside the confidence interval

Answer 16

C) 95% of the time, the true population parameter lies within the confidence interval

Question 17

What is the purpose of a t-test?

A) To compare the variances of two populations
B) To compare the means of two populations
C) To test the independence of two variables
D) To test the relationship between two variables

Answer 17

B) To compare the means of two populations

Question 18

values wanted to explain or forecast; values depend on something else; denote it as y

Answer 18

Dependent Variable

Question 19

explains the other one; denote it as x

Answer 19

Independent Variable

Question 20

point where the regression line crosses the Y-axis, representing the value of Y when X is zero

Answer 20

intercept

Question 21

What does the coefficient of determination (R2) indicate?

A) The strength of the linear relationship between two variables
B) The percentage of variation in the dependent variable explained by the independent variable
C) The slope of the regression line
D) The correlation between two variables

Answer 21

B) The percentage of variation in the dependent variable explained by the independent variable

Question 22

explaining or predicting a single Y variable from two or more X variables

Answer 22

Multiple Regression Analysis

Question 23

occurs when independent variables in a regression model are highly correlated

Answer 23

Multicollinearity

Question 24

Which of the following best describes heteroscedasticity in regression analysis?

A) The error terms have constant variance
B) The error terms have increasing or decreasing variance
C) The error terms are normally distributed
D) The error terms are autocorrelated

Answer 24

B) The error terms have increasing or decreasing variance

Question 25

means that the variance of the error terms changes across observations

Answer 25

Heteroscedasticity

Question 26

to find the relationships between two data factors

Answer 26

Logistic Regression

Question 27

In logistic regression, what type of dependent variable is used? A) Continuous B) Ordinal C) Nominal D) Binary

Answer 27

D) Binary

Question 28

Binary Explanation: Logistic regression is used for modeling binary (____) outcomes

Answer 28

(dichotomous)

Question 29

What is the purpose of an ANOVA test? A) To compare the means of two groups B) To compare the variances of two groups C) To compare the means of three or more groups D) To test the independence of two categorical variables

Answer 29

C) To compare the means of three or more groups

Question 30

In ANOVA, what does a significant F-test indicate? A) All group means are equal B) At least one group mean is different C) The variances are equal across groups D) There is a linear relationship between groups

Answer 30

B) At least one group mean is different

Question 31

What is the null hypothesis in a chi-square test of independence? A) The two variables are independent B) The two variables are dependent C) The two variables have equal variances D) The two variables have equal means

Answer 31

A) The two variables are independent

Question 32

purpose of this test is to determine if a difference between observed data and expected data is due to chance, or if it is due to a relationship between the variables you are studying.

Answer 32

chi-square test

Question 33

In a chi-square test, what is the expected frequency? A) The observed frequency in each category B) The frequency expected if the null hypothesis is true C) The sum of observed frequencies D) The total number of observations

Answer 33

B) The frequency expected if the null hypothesis is true

Question 34

Which of the following is a characteristic of a simple random sample? A) Each member of the population has an equal chance of being selected B) The population is divided into subgroups and samples are taken from each subgroup C) Samples are chosen based on convenience D) Samples are chosen based on specific characteristics

Answer 34

A) Each member of the population has an equal chance of being selected

Question 35

What is stratified sampling? A) Dividing the population into strata and randomly selecting samples from each stratum B) Selecting samples based on convenience C) Selecting every nth member of the population D) Grouping the population into clusters and randomly selecting clusters

Answer 35

A) Dividing the population into strata and randomly selecting samples from each stratum

Question 36

What is the main advantage of using a larger sample size? A) It reduces the population size B) It increases the standard error C) It increases the accuracy of the sample mean D) It reduces the variability of the population

Answer 36

C) It increases the accuracy of the sample mean

Question 37

The coefficient of variation (CV) is measured in terms of what unit? A) same unit with the data B) squared unit C) percent D) square root of the given unit

Answer 37

C) percent

Question 38

standardized measure of the dispersion of a probability distribution or frequency distribution

Answer 38

coefficient of variation (CV)

Question 39

What is the shape of the normal distribution? A) Skewed left B) Skewed right C) Symmetrical bell-shaped D) Uniform

Answer 39

C) Symmetrical bell-shaped

Question 40

Which of the following best describes the central limit theorem? A) The sum of a large number of random variables is normally distributed B) The mean of a large number of random variables is normally distributed C) The variance of a large number of random variables is normally distributed D) The median of a large number of random variables is normally distributed

Answer 40

B) The mean of a large number of random variables is normally distributed

Question 41

states that the distribution of the sample mean approaches a normal distribution as the sample size becomes large

Answer 41

central limit theorem

Question 42

What does the term ”statistical power” refer to? A) The probability of making a Type I error B) The probability of making a Type II error C) The probability of correctly rejecting the null hypothesis D) The probability of accepting the null hypothesis

Answer 42

C) The probability of correctly rejecting the null hypothesis

Question 43

likelihood that a test will detect an effect when there is an effect to be detected

Answer 43

Statistical power

Question 44

What is the purpose of standardizing a variable? A) To change the variable’s mean to 1 B) To change the variable’s standard deviation to 0 C) To make the variable’s mean 0 and standard deviation 1 D) To convert the variable to a binary format

Answer 44

C) To make the variable’s mean 0 and standard deviation 1

Question 45

What is the purpose of a boxplot? A) To display the frequency of data B) To show the distribution of data based on a five-number summary C) To display the relationship between two variables D) To show the central tendency of data

Answer 45

B) To show the distribution of data based on a five-number summary

Question 46

visually displays the distribution of a dataset using the minimum, first quartile, median, third quartile, and maximum

Answer 46

Boxplot

Question 47

Which of the following statements about measures of variability must always be true if the standard deviation is equal to 1? A) The standard deviation is equal to the variance B) The standard deviation is less than the variance C) The standard deviation is greater than the variance D) None of the above

Answer 47

A) The standard deviation is equal to the variance

Question 48

Which of the following statements is true about a normal distribution? A) It is skewed to the right B) It is skewed to the left C) It is symmetric about the mean D) It has two peaks

Answer 48

C) It is symmetric about the mean

Question 49

What is the purpose of using a scatter plot? A) To display the frequency of different categories B) To show the relationship between two variables C) To compare the means of different groups D) To show the distribution of a single variable

Answer 49

B) To show the relationship between two variables

Question 50

What does the null hypothesis in hypothesis testing typically state? A) There is an effect or difference B) There is no effect or difference C) The effect or difference is greater than expected D) The effect or difference is less than expected

Answer 50

B) There is no effect or difference

Question 51

typically states that there is no effect or difference, serving as a starting point for statistical testing

Answer 51

null hypothesis

Question 52

What is a confidence interval? A) A range of values within which the sample mean lies B) A range of values within which the population parameter lies C) The range between the smallest and largest values in a dataset D) The range of values within one standard deviation of the mean

Answer 52

B) A range of values within which the population parameter lies

Question 53

What is the main purpose of a control group in an experiment? A) To provide a comparison for the experimental group B) To increase the sample size C) To reduce the variability within the data D) To eliminate the need for random sampling

Answer 53

A) To provide a comparison for the experimental group

Question 54

In the context of regression analysis, what is multiple regression used for? A) Analyzing the effect of a single independent variable on a dependent variable B) Analyzing the effect of multiple independent variables on a dependent variable C) Analyzing the effect of a single independent variable on multiple dependent variables D) Analyzing the effect of multiple independent variables on multiple dependent variables

Answer 54

B) Analyzing the effect of multiple independent variables on a dependent variable

Question 55

What is the difference between a bar chart and a histogram? A) A bar chart displays categorical data, while a histogram displays numerical data B) A bar chart displays numerical data, while a histogram displays categorical data C) A bar chart is used for one variable, while a histogram is used for two variables D) There is no difference; they are the same

Answer 55

A) A bar chart displays categorical data, while a histogram displays numerical data

Question 56

What is an outlier in a dataset? A) A value that is exactly equal to the mean B) A value that is very different from the other values in the dataset C) A value that occurs most frequently D) A value that falls within the interquartile range

Answer 56

B) A value that is very different from the other values in the dataset

Question 57

Which of the following refers to the degree of flatness or peakedness of a curve? A) Central Tendency B) Dispersion C) Skewness D) Kurtosis

Answer 57

D) Kurtosis

Question 58

measures the ”tailedness” of the distribution, indicating whether the data are heavy-tailed or light-tailed relative to a normal distribution. It provides information about the height and sharpness of the central peak relative to that of a normal distribution

Answer 58

Kurtosis

Question 59

measures the ”tailedness” of the distribution, indicating whether the data are heavy-tailed or light-tailed relative to a normal distribution. It provides information about the height and sharpness of the central peak relative to that of a normal distribution

Answer 59

Kurtosis

Question 60

represents the size of distribution of values that are expected for a specific variable.

Answer 60

Dispersion

Question 61

measure of the asymmetry of a distribution; right (positive) or left (negative) skewness

Answer 61

Skewness