1. How do you calculate class width (W)?

A. \( W = \frac{R}{K} \) where R is range and K is number of classes B. \( W = R \times K \) C. \( W = R + K \) D. \( W = K - R \)

2. How does a pie chart represent data?

A. Using vertical bars proportional to values B. Using sectors with angles proportional to the frequency of items C. Using lines to show trends over time D. By listing raw frequencies in a table

3. Which of the following measures of central tendency is best for skewed data?

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

4. Which of these is NOT a feature of a bar chart?

A. Bars are separated by equal spaces B. Length or height of bars is proportional to data values C. Bars overlap each other D. Categories are shown on one axis and frequencies on the other

5. What is the primary purpose of graphical presentation of data?

A. To complicate data interpretation B. To hide misleading data trends C. To make information easier to understand and interpret D. To remove outliers from the dataset

6. What type of variable is "temperature"?

A. Nominal variable B. Discrete variable C. Continuous variable D. Ordinal variable

7. What is the main purpose of using statistical methods in data analysis?

A. To collect raw, unprocessed data B. To organize and clarify data relationships and classifications C. To ignore variability in data D. To produce data without any summarization

8. What is the purpose of class boundaries in frequency distribution?

A. They specify the exact maximum data value only B. They define clear dividing points between adjacent class intervals C. They list frequencies for each class D. They indicate cumulative totals for the data

9. What is an advantage of direct observation as a data collection method?

A. It is very fast B. Data collected is free from exaggeration C. It is inexpensive for large group studies D. It requires no supervision during data collection

10. Which data collection method involves direct interaction through a phone call?

A. Mailed questionnaire B. Direct observation C. Telephone interview D. Face-to-face interview

11. What does a frequency table show?

A. The relationship between two variables B. The number of observations within each class or category C. The average values of the data set D. The total number of data points in a study

12. What is the main advantage of using a pie chart to represent data?

A. It shows changes over time effectively B. It displays the frequency of individual data points clearly C. It visually shows each category’s proportion relative to the whole D. It separates data into equal intervals for easy comparison

13. What is the defining feature of an exclusive class interval?

A. The upper limit of one class equals the lower limit of the next class B. Both lower and upper limits are included in the class C. The class contains open-ended boundaries D. The class intervals do not overlap or touch

14. How do you find the class mark (midpoint) of a class interval?

A. Multiply lower and upper limits B. Add lower and upper limits and divide by two C. Subtract lower limit from upper limit D. Add frequencies of adjacent classes

15. How is the sectorial angle for a pie chart calculated for each category?

A. \( \text{Sector Angle} = \frac{\text{Frequency}}{\text{Total}} \times 360^\circ \) B. \( \text{Sector Angle} = \frac{\text{Frequency}}{\text{Total}} \times 100 \) C. \( \text{Sector Angle} = \text{Frequency} \times 360^\circ \) D. \( \text{Sector Angle} = 360^\circ - \text{Frequency} \)

16. What is a key feature of inferential statistics?

A. Summarizing data through charts and tables B. Making generalizations about a population from sample data C. Collecting raw data D. Organizing data into frequency tables

17. Which of the following best describes a continuous variable?

A. A variable that takes only integer values B. A variable that can take any value within a given range C. A variable counted in distinct steps D. A variable with no numerical values

18. In the exclusive method of classification, how are class intervals arranged?

A. So that the upper and lower limits overlap B. To include only whole numbers without decimals C. So that the upper limit of one class is the lower limit of the next class D. Using open-ended ranges without limits

19. How are frequencies recorded in a frequency table?

A. Using numbers only B. Using tally marks and numbers C. Using percentages only D. Using names of classes only

20. What does the mode indicate in a dataset?

A. The value that appears most frequently B. The average of all values C. The middle value after sorting D. The range of the data

21. What is the formula proposed by Sturges to determine the number of classes (K) in a frequency distribution?

A. \( K = 10 + 3.322 \log N \) B. \( K = 1 + 3.322 \log N \) C. \( K = \sqrt{N} \) D. \( K = \frac{N}{10} \)

22. Which characteristic belongs to secondary data?

A. Collected firsthand by the researcher B. Typically obtained from existing publications or databases C. Always expensive to acquire D. Always collected recently

23. What type of graph uses rectangular bars with heights proportional to the values represented?

A. Pie chart B. Line graph C. Bar chart D. Histogram

24. What is the purpose of statistical methods?

A. To interpret graphs and charts only B. To classify data and analyze relationships between variables C. To store data in databases D. To collect primary data only

25. What is the formula to determine the number of classes (K) using Sturges’ formula?

A. \(K = \sqrt{N}\) B. \(K = 3.322 \log N\) C. \(K = N / 10\) D. \(K = \log(N) / 3.322\)

26. What does an inclusive class interval ensure in classification?

A. Overlapping between class intervals B. Both lower and upper limits are included in each class C. No inclusion of boundaries D. Open-ended categories

27. Which statement correctly describes continuous variables?

A. They take only integer values B. They have unlimited possible values within a range, typically measured C. They are counted rather than measured D. They are qualitative and categorical variables

28. In what situation would open-end class intervals be used?

A. When all data values are known exactly B. When there are extremely high or low values without clear boundary C. When data are categorical only D. When classes must be mutually exclusive

29. Which of the following data is quantitative?

A. Colors of cars B. Heights of students C. Types of fruits D. Names of cities

30. What is an example of primary data?

A. Government statistical bulletins B. Data collected by direct observation in a laboratory C. Newspaper reports D. Research journals

31. What is cumulative frequency?

A. Frequency divided by the total number of observations B. Sum of frequencies up to a given class C. Frequency of the last class only D. Highest frequency in the table

32. Which of the following is NOT an advantage of using interviews as a data collection method?

A. It is best suited to situations requiring in-depth study B. It often results in reliable and genuine responses C. It is quick and inexpensive for large groups D. It helps understand problems not fully clear to respondents

33. What type of variable is "number of students in a class"?

A. Continuous variable B. Discrete variable C. Qualitative variable D. Nominal variable

34. How is the range (R) of a data set calculated?

A. \( R = \text{smallest observation} - \text{largest observation} \) B. \( R = \text{largest observation} + \text{smallest observation} \) C. \( R = \text{largest observation} - \text{smallest observation} \) D. \( R = \text{average of observations} \)

35. How is a pie chart constructed?

A. Using rectangular bars proportional to values B. Dividing a circle into sectors proportional to frequencies C. Plotting data points on a Cartesian plane D. Connecting line segments between data points

36. What is the difference between primary and secondary data?

A. Primary data is collected by others; secondary data is collected firsthand B. Primary data is quantitative; secondary data is qualitative only C. Primary data is first-hand, collected directly for the study; secondary data is obtained from existing sources D. Primary data is always more reliable than secondary data

37. Which of the following is a disadvantage of mailed questionnaires?

A. High cost B. Risk of misunderstanding questions leading to inaccurate responses C. Allows for consultation with the respondent D. Fast collection of data

38. Why are bar charts useful in statistics?

A. They show data proportions as sectors of a circle B. They display data using rectangles with lengths proportional to values C. They represent data points connected by lines over time D. They summarize data using numerical averages

39. Which branch of statistics is concerned with drawing conclusions about a population from sample data?

A. Descriptive statistics B. Inferential statistics C. Summary statistics D. Graphical statistics

40. What is an example of a disadvantage when using telephone interviews to collect data?

A. Difficult to monitor interviewers B. Slow responses in urban areas C. Responses depend on respondent's mood D. Expensive compared to mailed questionnaires

41. What is a discrete variable?

A. A variable measured in infinite decimal places B. A variable that changes in distinct steps and takes integer values C. A variable that changes continuously D. A variable without any assigned values

42. What is the first step in creating a frequency distribution from raw data?

A. Find the cumulative frequencies B. Determine the number of observations C. Calculate the range of data D. Create bar chart

43. Which is a key limitation of mailed questionnaires?

A. They guarantee 100% response rate B. It’s easy to monitor respondents’ understanding C. They may have low return rates and poorly motivated responses D. They are expensive to administer

44. What does a frequency table display?

A. The sum of all data points B. The number of observations in each class or category C. The mean of all observations D. The median of the data set

45. Which method of data collection is particularly useful for illiterate respondents?

A. Mailed questionnaire B. Direct observation C. Interviewing D. Online survey

46. Which of the following is NOT an advantage of an interview method of data collection?

A. Provides reliable responses with experienced interviewers B. Suitable for complex problems C. Time-consuming and expensive D. Allows for probing and follow-up questions

47. What does cumulative frequency represent?

A. The number of observations in a specific class alone B. The sum of frequencies up to and including a given class C. The average frequency of all classes D. The probability of occurrence of a class

48. In terms of data collection, what is a census?

A. Studying a representative part of the population B. Complete enumeration of all units in the population C. Collecting data from secondary sources D. Observation in a controlled laboratory setting

49. What are class boundaries?

A. Exact limits separating adjacent classes B. The midpoint of a class interval C. The frequency of a class D. Open-ended values in a table

50. Why is graphical representation important in statistics?

A. It complicates the understanding of data B. It helps present data in a clear and engaging manner C. It eliminates the need for tabular data D. It only shows partial data sets