1. What is a parameter in statistics? 7. Which statement best describes an estimator that is accurate but 13.
ator that is accurate but 13. When the population variance is known, which distribution is
A) A numerical measure that describes a sample not precise? typically used to calculate confidence intervals for the population
B) A numerical measure that describes a population and does not A) Estimates are close to the true value and close to each other mean?
change B) Estimates are far from the true value but close to each other A) t-distribution
C) A random sample taken from a population C) Estimates are close to the true value but spread out B) Normal distribution (z-distribution)
D) A formula used to compute estimates D) Estimates are neither close to the true value nor to each other C) Chi-square distribution
D) F-distribution
2. A random sample means: 8. What is an interval estimate?
A) A sample with no fixed size A) A single value used to estimate a parameter 14. As the degrees of freedom increase, the t-distribution:
B) Every element in the population has an equal chance of being B) A formula for calculating mean and variance A) Becomes more spread out
chosen C) A range of values used to estimate an unknown parameter B) Approaches the standard normal distribution
C) Sampling only the elements you want D) A sample that has equal chance of selection C) Becomes skewed to the right
D) A sample that is biased D) Becomes more peaked than the normal distribution
9. What does the confidence level in a confidence interval indicate?
3. What is the sample mean? A) The percentage of times the interval contains the parameter in 15. In a market survey of 300 people, 138 preferred a particular
A) The average of the entire population repeated sampling brand. To estimate the proportion of all consumers who prefer that
B) The mean of a random sample taken from the population B) The precision of the estimate brand, you would calculate:
C) The median of the sample data C) The size of the sample used A) A point estimate only
D) The range of the data values D) The midpoint of the interval B) A confidence interval for the population proportion
C) The mean of all survey respondents
4. What does the term point estimate refer to? 10. If you want to be more confident that your interval estimate D) The sample size required for the survey
A) A range of values that likely contains the parameter contains the true parameter, you should:
B) A single value computed from sample data used to estimate a A) Use a lower confidence level (e.g., 90%) 16. What is a hypothesis in statistics?
parameter B) Use a higher confidence level (e.g., 99%) A) A random guess without basis
C) The formula to calculate the mean C) Decrease the sample size B) A proposition or assumption about a population parameter for
D) The average of the confidence intervals D) Ignore the margin of error testing
C) A method of data collection
5. When an estimator is described as unbiased, it means: 11. Increasing the confidence level from 95% to 99% will: D) The result of an experiment
A) It always equals the parameter A) Increase precision but lower confidence 17. Who are some of the key contributors to the development of
B) It has the smallest possible variance B) Decrease both precision and confidence hypothesis testing?
C) The expected value of the estimator equals the true parameter C) Increase confidence but decrease precision (wider interval) A) Albert Einstein and Isaac Newton
value D) Not affect the confidence interval B) Sir Ronald Fisher, Jerzy Neyman, Karl Pearson, Egon Pearson
D) It produces the same result every time C) Thomas Bayes and Pierre-Simon Laplace
12. The margin of error is: D) John Tukey and Florence Nightingale
6. What is the Minimum Variance Unbiased Estimator (MVUE)? A) The midpoint of the confidence interval
A) The estimator with the highest variance B) The maximum expected difference between the sample estimate 18. Hypothesis testing is primarily used to:
B) The estimator with the smallest variance among unbiased and the true population parameter A) Summarize data using charts
estimators C) The size of the sample B) Make statistical decisions based on experimental data
C) The point estimate with the widest interval D) The average of all sample means C) Create samples from populations
D) The estimator that always overestimates the parameter D) Calculate descriptive statistics
19. Which of the following is NOT one of the three methods used to C) If a parameter is different from a given value in either direction C) Data collected from two different populations
test hypotheses? D) If the sample size is too small D) Data that is unrelated
A) Traditional Method
B) P-value Method 26. A two-tailed test is applied when: 32. In a bivariate data set, the independent variable is:
C) Confidence Interval Method A) Testing if a parameter equals a specific value A) The variable being predicted or explained
D) Regression Method B) Testing if a parameter is different (either higher or lower) from a B) The variable that influences or predicts another variable
specific value C) The variable that cannot be changed
20. What is the first step in the five-step hypothesis testing C) Testing only increases in a parameter D) The variable that is always qualitative
procedure? D) Testing only decreases in a parameter
A) Compute the test statistic 33. Which of the following is an example of an independent
B) Make a decision and conclusion 27. Which phrase best describes the critical region or rejection variable?
C) Formulate the null hypothesis and alternative hypothesis region? A) Amount of detergent used in cleaning
D) Determine the critical region A) Range of values where the null hypothesis is accepted B) Amount of stain removed from clothes
B) Range of values where the null hypothesis is rejected C) Height of a student
21. The level of significance (α) is: C) The set of all possible values of the sample mean D) Weight of a student
A) The probability of accepting the null hypothesis when it is false D) The range for calculating confidence intervals
B) The probability of rejecting the null hypothesis when it is true 34. A scatter diagram is used to:
C) The confidence interval 28. The p-value in hypothesis testing is: A) Show frequency distributions
D) The sample mean A) The sample proportion B) Display the relationship between two variables graphically
B) The probability of obtaining a test statistic at least as extreme as C) Calculate averages of data sets
22. In hypothesis testing, the null hypothesis (H₀) generally states: the one observed, assuming the null hypothesis is true D) Show cause and effect conclusively
A) The effect or difference exists C) The difference between sample mean and population mean
B) No effect or no difference exists D) The level of significance 35. On a Cartesian plane used in scatter plots, the x-axis usually
C) The sample data is biased represents:
D) The experiment failed 29. If the p-value is less than the level of significance (α), the A) Dependent variable
decision is to: B) Independent variable
23. An alternative hypothesis (H₁ or Ha) is: A) Fail to reject the null hypothesis C) The data range
A) The hypothesis to be tested B) Reject the null hypothesis D) The correlation coefficient
B) The opposite of the null hypothesis and what the researcher C) Accept the null hypothesis
wants to prove D) Increase the sample size 36. What does linearity in a scatter diagram mean?
C) Always a two-tailed test A) Data points are spread randomly
D) A type of error 30. In the example given, a public official wants to determine if B) Data points follow a straight line pattern
there is a decrease in monthly power consumption. What type of C) Data points form a circle
24. What does a left-tailed test investigate? test should be used? D) Data points have no relationship
A) Whether the parameter is greater than a specific value A) Right-tailed test
B) Whether the parameter is less than a specific value B) Left-tailed test 37. When points in a scatter plot are widely scattered, what does it
C) Whether the parameter is not equal to a specific value C) Two-tailed test indicate about the strength of the relationship?
D) Whether the parameter equals zero D) No test needed A) The relationship is strong
B) The relationship is weak
25. A right-tailed test is used when you want to test: 31. What is bivariate data? C) The relationship is positive
A) If a parameter is less than a given value A) Data that contains only one variable D) There is no relationship
B) If a parameter is greater than a given value B) Data that contains two variables and their relationship is studied
38. What does a positive slope in a scatter diagram indicate? A) 15
A) As one variable increases, the other decreases B) 20
B) There is no relationship between variables C) 25
C) As one variable increases, the other increases D) 30
D) The variables are independent
45. What is the main use of regression analysis?
A) To graph scatter plots only
39. What is the purpose of correlation analysis? B) To describe the pattern of data without making predictions
A) To summarize data in tables C) To develop an equation that predicts one variable based on
B) To determine if a relationship exists between two variables, and another
its strength and direction D) To determine if variables are independent
C) To predict the exact value of one variable from another
D) To calculate sample size
40. The correlation coefficient (r) measures:
A) The average value of two variables
B) The strength and direction of a linear relationship between two
variables
C) The difference between two variables
D) The slope of the regression line
41. A correlation coefficient value of 0.84 indicates:
A) A weak negative correlation
B) A strong positive correlation
C) No correlation
D) A perfect positive correlation
42. What is the regression line?
A) A line that connects all data points
B) The line of best fit that predicts values of the dependent variable
from the independent variable
C) The horizontal axis in a scatter plot
D) The average of all independent variable values
43. How do you find the regression equation of a line?
A) Using the slope and y-intercept of the best-fit line
B) Using the correlation coefficient only
C) By calculating the mean of the dependent variable
D) By plotting the independent variable on the y-axis
44. If the regression equation is y=2 x +5, what is the predicted
value of when x=10 ?
