Sample Quizzes For Preparation: Data And Its Collection
O Level and IGCSE Statistics – Quiz: 1. Data and Its Collection
1. What is the main reason for using a sample instead of a census?
A. To eliminate bias
B. To collect more qualitative data
C. To save time and cost
D. To ensure 100% accuracy
2. Which of the following best defines a population in statistics?
A. A collection of numerical values
B. A large number of random samples
C. The entire group being studied
D. The first 100 individuals in a list
3. What is a key characteristic of simple random sampling?
A. Selecting from fixed quotas
B. Stratifying based on groups
C. Every member has an equal chance
D. Choosing people who are easiest to access
4. Which sampling method divides the population into strata before sampling?
A. Systematic sampling
B. Quota sampling
C. Simple random sampling
D. Stratified sampling
5. Which is an example of discrete quantitative data?
A. Height of students
B. Temperature in Celsius
C. Number of siblings
D. Weight in kilograms
6. What is meant by qualitative data?
A. Data measured using instruments
B. Data that can be counted
C. Data expressed in categories or words
D. Data from biased sources
7. What is a survey?
A. A method for conducting experiments
B. A form of secondary data
C. A method to collect data using questions
D. A way to analyze graphs
8. Which method is likely to introduce bias?
A. Using random numbers for selection
B. Interviewing only friends
C. Stratified sampling
D. Systematic sampling
9. Which of the following is a continuous variable?
A. Number of students
B. Shoe size
C. Height
D. Number of cars
10. Which of the following best describes a representative sample?
A. One that includes the largest number of people
B. One that includes only experts
C. One that reflects the characteristics of the population
D. One that is easy to collect
11. What is the main purpose of using stratified sampling?
A. To eliminate continuous data
B. To ignore certain subgroups
C. To ensure each subgroup is proportionally represented
D. To speed up analysis
12. What kind of question is: “What is your opinion on school lunches?”
A. Closed
B. Biased
C. Open
D. Numerical
13. Which tool is best for generating random samples?
A. Calculator
B. Random number table
C. Pie chart
D. Questionnaire
14. Which term refers to a variable that can only take certain values?
A. Continuous
B. Qualitative
C. Discrete
D. Subjective
15. Which of the following is a risk of using a small sample?
A. Higher accuracy
B. Greater representativeness
C. Increased bias
D. Easier data handling
16. A student selects every 5ᵗʰ person from a school list. This is an example of:
A. Stratified sampling
B. Systematic sampling
C. Random sampling
D. Biased sampling
17. What is a census?
A. Data collection from a sample
B. Interviewing people at random
C. Studying a small group
D. Collecting data from the entire population
18. Which type of question allows more detailed responses?
A. Open
B. Closed
C. Multiple choice
D. Yes/No
19. What is bias in sampling?
A. Equal chance of selection
B. Data that is always correct
C. Error that favors certain outcomes
D. Random selection from a population
20. What is a disadvantage of using open questions in surveys?
A. They are too brief
B. They may be unclear
C. They are harder to analyze
D. They have low validity
21. The term “verstehen” relates to:
A. Stratified sampling
B. Positivist methods
C. Understanding human behavior
D. Secondary data collection
22. A shopkeeper surveys every customer who enters between 2–3 PM. What is the issue?
A. The survey is random
B. There is no bias
C. The sample may not represent all customers
D. The sample is stratified
23. What does ‘generalizability’ refer to in data collection?
A. The accuracy of calculations
B. Applying results to a whole population
C. The length of the questionnaire
D. The structure of questions
24. What is quota sampling based on?
A. Random numbers
B. Selecting equal groups
C. Interviewer judgment based on categories
D. Total population count
25. What is the first step in designing a survey?
A. Distribute the questionnaire
B. Define the objective
C. Analyze results
D. Choose a random sample
26. If a variable has both numeric and continuous characteristics, it is called:
A. Qualitative
B. Categorical
C. Quantitative continuous
D. Discrete
27. Which of the following is NOT a good way to avoid bias?
A. Random sampling
B. Stratified sampling
C. Leading questions
D. Large sample size
28. A graph showing temperature over time involves what type of data?
A. Qualitative
B. Discrete
C. Continuous
D. Quota
29. Which variable changes in response to the independent variable?
A. Control
B. Continuous
C. Dependent
D. Discrete
30. A postal survey is likely to have what limitation?
A. Too many responses
B. No bias
C. Low response rate
D. Complete population coverage
Marking Key and Detailed Explanations
| Q | Answer | Explanation |
|---|---|---|
| 1 | C | Samples reduce time and cost while still giving good estimates |
| 2 | C | A population includes the entire group under study |
| 3 | C | Equal chance is key in simple random sampling |
| 4 | D | Stratified sampling divides population into strata |
| 5 | C | Discrete data takes fixed values (e.g., 0, 1, 2…) |
| 6 | C | Qualitative data = descriptive, non-numeric |
| 7 | C | Surveys collect data via structured questions |
| 8 | B | Choosing friends leads to non-representative, biased sample |
| 9 | C | Height can take any value in a range = continuous |
| 10 | C | A representative sample mirrors the population’s structure |
| 11 | C | Ensures all subgroups are proportionally sampled |
| 12 | C | Open questions allow detailed, free responses |
| 13 | B | Random number tables are used for random sampling |
| 14 | C | Discrete variables take only specific values |
| 15 | C | Small samples may not represent the full population accurately |
| 16 | B | Every 5ᵗʰ person = systematic sampling |
| 17 | D | Census = entire population is studied |
| 18 | A | Open questions = more in-depth but harder to analyze |
| 19 | C | Bias favors certain outcomes, making data unreliable |
| 20 | C | Open questions yield complex data that’s harder to code/analyze |
| 21 | C | Verstehen = understanding subjective human meanings |
| 22 | C | Sample only includes customers at one time of day |
| 23 | B | Generalizability = how well sample results apply to population |
| 24 | C | Quota sampling is based on set category targets |
| 25 | B | Always start by clearly defining survey objectives |
| 26 | C | Continuous quantitative variables can take any numeric value |
| 27 | C | Leading questions can influence answers and introduce bias |
| 28 | C | Temperature varies continuously |
| 29 | C | Dependent variable depends on the changes in independent variable |
| 30 | C | Postal surveys often have low response rates |