Question 1

Frame at least four appropriate multiple-choice options for following questions:

(i) Which of the following is the most important when you buy a new dress?

(ii) How often do you use computers?

(iii) Which of the newspapers do you read regularly?

(iv) Rise in the price of petrol is justified.

(v) What is the monthly income of your family?

Accepted Answer

This question asks you to create multiple-choice options for each of the given questions. For example:

(i) Which of the following is the most important when you buy a new dress?
Options:
A) Price
B) Colour
C) Brand
D) Comfort

(ii) How often do you use computers?
Options:
A) Daily
B) Weekly
C) Occasionally
D) Never

(iii) Which of the newspapers do you read regularly?
Options:
A) The Times of India
B) Hindustan Times
C) The Hindu
D) None

(iv) Rise in the price of petrol is justified.
Options:
A) Strongly agree
B) Agree
C) Disagree
D) Strongly disagree

(v) What is the monthly income of your family?
Options:
A) Less than Rs. 10,000
B) Rs. 10,000 - Rs. 20,000
C) Rs. 20,000 - Rs. 30,000
D) More than Rs. 30,000 — The question requires framing four options for each question to convert them into multiple-choice questions. The options should be relevant and cover possible answers that respondents might choose.

Question 2

Frame five two-way questions (with 'Yes' or 'No').

Accepted Answer

Two-way questions are those which can be answered with 'Yes' or 'No'. Examples:
1. Do you like to study Economics?
2. Have you ever used a computer?
3. Is your school located in the city?
4. Do you watch television daily?
5. Have you ever traveled outside your state? — Two-way questions are simple questions that expect a 'Yes' or 'No' answer. They are useful for straightforward data collection.

Question 3

State whether the following statements are True or False.

(i) There are many sources of data.

(ii) Telephone survey is the most suitable method of collecting data, when the population is literate and spread over a large area.

(iii) Data collected by investigator is called the secondary data.

(iv) There is a certain bias involved in the non-random selection of samples.

(v) Non-sampling errors can be minimised by taking large samples.

Accepted Answer

(i) True - There are many sources of data such as surveys, censuses, administrative records, etc.

(ii) True - Telephone surveys are suitable when the population is literate and spread over a large area.

(iii) False - Data collected by investigator is called primary data, not secondary data.

(iv) True - Non-random selection of samples introduces bias.

(v) False - Non-sampling errors cannot be minimized by increasing sample size; they arise due to other factors like measurement errors. — Each statement is evaluated based on definitions and concepts:
- Primary data is collected firsthand by the investigator.
- Secondary data is data collected by someone else.
- Non-sampling errors are different from sampling errors and are not reduced by increasing sample size.

Question 4

What do you think about the following questions? Do you find any problem with these questions? Describe.

(i) How far do you live from the closest market?
(ii) If plastic bags are only 5 per cent of our garbage, should it be banned?
(iii) Wouldn't you be opposed to increase in price of petrol?
(iv) Do you agree with the use of chemical fertilisers?
(v) Do you use fertilisers in your fields?
(vi) What is the yield per hectare in your field?

Accepted Answer

This question asks to analyze the given questions for any problems such as ambiguity, leading questions, or difficulty in answering.

(i) 'How far do you live from the closest market?' - May be difficult for some respondents to estimate exact distance.

(ii) 'If plastic bags are only 5 per cent of our garbage, should it be banned?' - This is a leading question as it suggests a small percentage.

(iii) 'Wouldn't you be opposed to increase in price of petrol?' - Leading question, suggests the expected answer is opposition.

(iv) 'Do you agree with the use of chemical fertilisers?' - May be biased; better to ask neutrally.

(v) 'Do you use fertilisers in your fields?' - Clear and direct.

(vi) 'What is the yield per hectare in your field?' - May be difficult if the farmer does not know exact figures. — Good survey questions should be clear, unbiased, and easy to answer. Leading or ambiguous questions can affect the quality of data collected.

Question 5

You want to do a research on the popularity of Vegetable Atta Noodles among children. Design a suitable questionnaire for collecting this information.

Accepted Answer

A suitable questionnaire may include:
1. Do you like Vegetable Atta Noodles? (Yes/No)
2. How often do you eat Vegetable Atta Noodles? (Daily/Weekly/Monthly/Never)
3. What is your favourite flavour of Vegetable Atta Noodles?
4. Where do you usually buy Vegetable Atta Noodles? (Shop/School Canteen/Other)
5. Would you recommend Vegetable Atta Noodles to your friends? (Yes/No)
6. What do you like most about Vegetable Atta Noodles? (Taste/Price/Packaging/Other)
7. Are there any improvements you would like to see in Vegetable Atta Noodles?

This questionnaire collects both qualitative and quantitative data about popularity. — The questionnaire should be simple, clear, and cover different aspects of popularity such as preference, frequency, and opinion.

Question 6

In a village of 200 farms, a study was conducted to find the cropping pattern. Out of the 50 farms surveyed, 50% grew only wheat. What is the population and the sample size?

Accepted Answer

Population: The total number of farms in the village = 200 farms.
Sample size: The number of farms surveyed = 50 farms. — Population refers to the entire group under study (all 200 farms). Sample size is the subset selected for study (50 farms).

Question 7

Give two examples each of sample, population and variable.

Accepted Answer

Examples:
Population:
1. All students in your school.
2. All households in your city.

Sample:
1. 100 students selected from your school.
2. 50 households surveyed in your city.

Variable:
1. Height of students.
2. Monthly income of households. — Population is the entire group; sample is a subset; variable is a characteristic that can vary among units.

Question 8

Which of the following methods give better results and why?
(a) Census
(b) Sample

Accepted Answer

Census gives better results because it involves collecting data from the entire population, so it is more accurate and complete. However, it is time-consuming and expensive.
Sample surveys are quicker and less expensive but may have sampling errors and may not represent the entire population perfectly. — Census covers all units, eliminating sampling error, but is costly. Sample surveys are practical but may have errors due to sampling.

Question 9

Which of the following errors is more serious and why?
(a) Sampling error
(b) Non-Sampling error

Accepted Answer

Non-sampling errors are more serious because they arise from mistakes in data collection, recording, or processing and can cause bias. Sampling errors can be reduced by increasing sample size, but non-sampling errors are harder to detect and correct. — Sampling errors are due to chance and can be controlled by sample size. Non-sampling errors are systematic and affect data quality more severely.

Question 10

Suppose there are 10 students in your class. You want to select three out of them. How many samples are possible?

Accepted Answer

Number of ways to select 3 students out of 10 = Combination of 10 taken 3 = 10C3 = 10! / (3! * 7!) = (10 × 9 × 8) / (3 × 2 × 1) = 120 samples. — Use combination formula nCr = n! / (r! (n-r)!) to find number of samples.

Question 11

Discuss how you would use the lottery method to select 3 students out of 10 in your class.

Accepted Answer

To use the lottery method:
1. Assign a unique number from 1 to 10 to each student.
2. Write these numbers on identical slips of paper.
3. Mix the slips thoroughly in a box or bag.
4. Draw three slips one by one without looking.
5. The students whose numbers are drawn form the sample.
This method ensures random selection. — Lottery method is a simple random sampling technique where each unit has equal chance of selection.

Question 12

Does the lottery method always give you a random sample? Explain.

Accepted Answer

Yes, the lottery method gives a random sample provided that:
- Each unit has an equal chance of being selected.
- The slips are mixed thoroughly.
- The selection is done without bias.
If these conditions are met, the sample is random. — Randomness depends on equal probability and unbiased selection. The lottery method is a simple way to achieve this.

Question 13

Explain the procedure for selecting a random sample of 3 students out of 10 in your class by using random number tables.

Accepted Answer

Procedure:
1. Assign numbers 1 to 10 to each student.
2. Use a random number table.
3. Start from any point in the table and read numbers sequentially.
4. Select the numbers between 1 and 10 as sample units.
5. Continue until 3 unique numbers are selected.
6. The students corresponding to these numbers form the sample. — Random number tables provide unbiased random numbers to select samples fairly.

Question 14

Do samples provide better results than surveys? Give reasons for your answer.

Accepted Answer

Samples do not necessarily provide better results than surveys. Surveys can be of two types: census (survey of entire population) and sample survey.

- Census provides complete data but is costly and time-consuming.
- Sample surveys are quicker and less expensive but may have sampling errors.

Samples provide good results if properly selected and representative.

Therefore, samples are practical and efficient but not always better than full surveys. — The quality of results depends on method, sample size, and representativeness. Samples are often preferred for feasibility.

Question 15

In economics, what is the term used for quantities that vary from year to year or from crop to crop, and are generally represented by letters such as X, Y, or Z?

Accepted Answer

Variables — Variables are quantities that can change or vary over time or across different observations. In economics, variables such as production or price are often represented by letters like X, Y, or Z. Each value of a variable is called an observation.

C HA P T E R

C HA P T E R — Study Notes

1. INTRODUCTION

2. WHAT ARE THE SOURCES OF DATA?

3. HOW DO WE COLLECT THE DATA?

Practice Questions — C HA P T E R

All 8 Chapters in Statistics for Economics