Question 1

Identify data required to be maintained to perform the following services:
a) Declare exam results and print e-certificates
b) Register participants in an exhibition and issue biometric ID cards
c) To search for an image by a search engine
d) To book an OPD appointment with a hospital in a specific department

Accepted Answer

a) Data required: Student details (name, roll number, exam scores, grades), exam results data, certificate templates, digital signatures for e-certificates.
b) Data required: Participant details (name, contact info, photo), biometric data (fingerprints, iris scan), registration details, ID card templates.
c) Data required: Image metadata (tags, descriptions, file names), image content data (pixels, features), user query data, indexing data.
d) Data required: Patient details, hospital department details, doctor schedules, appointment slots, patient medical history. — For each service, the data required corresponds to the entities involved and the operations to be performed. For exam results, student and result data are essential. For exhibition registration, participant and biometric data are needed. For image search, metadata and image content data are collected and indexed. For OPD booking, patient and hospital schedule data are necessary.

Question 2

A school having 500 students wants to identify beneficiaries of the merit-cum means scholarship, achieving more than 75% for two consecutive years and having family income less than 5 lakh per annum.

Briefly describe data processing steps to be taken by the school to prepare the list of beneficiaries.

Accepted Answer

Data processing steps:
1. Data Collection: Collect student academic records for the last two years and family income details.
2. Data Validation: Verify accuracy of marks and income data.
3. Data Filtering: Select students with more than 75% marks in both years.
4. Income Filtering: From filtered students, select those with family income less than 5 lakh per annum.
5. Compilation: Prepare the final list of beneficiaries.
6. Reporting: Generate reports or certificates for the selected students. — The process involves collecting relevant data, validating it, applying filters based on marks and income criteria, and compiling the final list. This ensures only eligible students are identified.

Question 3

A bank ‘xyz’ wants to know about its popularity among the residents of a city ‘ABC’ on the basis of number of bank accounts each family has and the average monthly account balance of each person. Briefly describe the steps to be taken for collecting data and what results can be checked through processing of the collected data.

Accepted Answer

Steps for data collection:
1. Define data requirements: Number of bank accounts per family, average monthly balance per person.
2. Sampling: Select representative families from city ABC.
3. Data Collection: Use surveys, bank records, or interviews to gather data.
4. Data Validation: Check for accuracy and completeness.
5. Data Processing: Analyze data to find average accounts per family, average balances.

Results that can be checked:
- Popularity of bank xyz based on number of accounts.
- Average balance trends indicating customer wealth.
- Identification of areas with low or high bank penetration.
- Customer segmentation based on account and balance data. — Collecting accurate data and processing it helps the bank understand its market penetration and customer base, enabling targeted marketing and service improvements.

Question 4

Identify type of data being collected/generated in the following scenarios:

a) Recording a video
b) Marking attendance by teacher
c) Writing tweets
d) Filling an application form online

Accepted Answer

a) Recording a video: Unstructured data (video files).
b) Marking attendance by teacher: Structured data (attendance records).
c) Writing tweets: Semi-structured data (text with hashtags, mentions).
d) Filling an application form online: Structured data (form fields with defined formats). — Data types depend on format and structure. Videos are unstructured, attendance is structured, tweets have semi-structured elements, and online forms are structured.

Question 5

Consider the temperature (in Celsius) of 7 days of a week as 34, 34, 27, 28, 27, 34, 34. Identify the appropriate statistical technique to be used to calculate the following:

a) Find the average temperature.
b) Find the temperature Range of that week.
c) Find the standard deviation temperature.

Accepted Answer

Given temperatures: 34, 34, 27, 28, 27, 34, 34

a) Average temperature = (Sum of temperatures) / 7
= (34+34+27+28+27+34+34) / 7
= 218 / 7 ≈ 31.14°C

b) Temperature Range = Maximum - Minimum
= 34 - 27 = 7°C

c) Standard Deviation (σ):
Step 1: Calculate mean (μ) = 31.14
Step 2: Calculate squared deviations:
(34-31.14)²=8.18, (34-31.14)²=8.18, (27-31.14)²=17.14, (28-31.14)²=9.86, (27-31.14)²=17.14, (34-31.14)²=8.18, (34-31.14)²=8.18
Step 3: Sum of squared deviations = 8.18+8.18+17.14+9.86+17.14+8.18+8.18=76.86
Step 4: Variance = 76.86 / 7 ≈ 10.98
Step 5: Standard deviation = √10.98 ≈ 3.31°C — Average is calculated by summing all values and dividing by count. Range is difference between max and min values. Standard deviation measures spread of data around mean using squared deviations and square root.

Question 6

A school teacher wants to analyse results. Identify the appropriate statistical technique to be used along with its justification for the following cases:

a) Teacher wants to compare performance in terms of division secured by students in Class XII A and Class XII B where each class strength is same.
b) Teacher has conducted five unit tests for that class in months July to November and wants to compare the class performance in these five months.

Accepted Answer

a) Appropriate technique: Bar graph or Pie chart to compare divisions between two classes.
Justification: Divisions are categorical data; visual comparison helps identify differences.

b) Appropriate technique: Line graph or trend analysis.
Justification: To observe performance trends over time (five months), line graphs effectively show changes. — Categorical data like divisions are best compared using bar or pie charts. Time series data like monthly test scores are best analyzed using line graphs to observe trends.

Question 7

Suppose annual day of your school is to be celebrated. The school has decided to felicitate those parents of the students studying in classes XI and XII, who are the alumni of the same school. In this context, answer the following questions:

a) Which statistical technique should be used to find out the number of students whose both parents are alumni of this school?
b) How varied are the age of parents of the students of that school?

Accepted Answer

a) Statistical technique: Frequency distribution or count analysis.
Explanation: Counting number of students with both parents as alumni is a frequency count.

b) Statistical technique: Measure of dispersion such as standard deviation or variance.
Explanation: To find how varied the ages are, dispersion measures quantify spread of age data. — Frequency counts help identify number of occurrences. Measures of dispersion like standard deviation indicate variability in data such as ages.

Question 8

For the annual day celebrations, the teacher is looking for an anchor in a class of 42 students. The teacher would make selection of an anchor on the basis of singing skill, writing skill, as well as monitoring skill.

a) Which mode of data collection should be used?
b) How would you represent the skill of students as data?

Accepted Answer

a) Mode of data collection: Observation and rating scales or questionnaires.
Explanation: Teacher can observe students or use rating scales to assess skills.

b) Representation of skill data: Use categorical or ordinal data representation such as skill levels (e.g., Excellent, Good, Average) or numerical scores.
Explanation: Skills can be quantified or categorized for comparison. — Observation and rating scales provide qualitative and quantitative data. Representing skills categorically or numerically helps in selecting the best anchor.

Question 9

Differentiate between structured and unstructured data giving one example.

Accepted Answer

Structured Data:
- Organized in fixed fields within records or files.
- Easily searchable and stored in databases.
- Example: Student attendance records.

Unstructured Data:
- Not organized in a predefined manner.
- Difficult to search and analyze directly.
- Example: Video recordings or images. — Structured data follows a defined format making it easy to process. Unstructured data lacks a predefined format and requires special tools for analysis.

Question 10

The principal of a school wants to do following analysis on the basis of food items procured and sold in the canteen:

a) Compare the purchase and sale price of fruit juice and biscuits.
b) Compare sales of fruit juice, biscuits and samosa.
c) Variation in sale price of fruit juices of different companies for same quantity (in ml).

Create an appropriate dataset for these items (fruit juice, biscuits, samosa) by listing their purchase price and sale price. Apply basic statistical techniques to make the comparisons.

Accepted Answer

Dataset example:
| Item       | Purchase Price (₹) | Sale Price (₹) |
|------------|--------------------|----------------|
| Fruit Juice| 20                 | 30             |
| Biscuits   | 10                 | 15             |
| Samosa     | 8                  | 12             |

Analysis:
a) Compare purchase and sale price of fruit juice and biscuits:
- Calculate profit = Sale Price - Purchase Price
- Fruit Juice profit = 30 - 20 = ₹10
- Biscuits profit = 15 - 10 = ₹5
- Fruit juice has higher profit margin.

b) Compare sales:
- Use sales quantity data (assumed or collected) to compare total sales.
- Represent using bar charts or pie charts.

c) Variation in sale price of fruit juices:
- Collect sale prices of fruit juices from different companies.
- Calculate range, mean, and standard deviation to analyze variation.

Basic statistical techniques like mean, range, and bar charts help in comparison. — Creating a dataset helps organize data for analysis. Profit calculation compares purchase and sale prices. Statistical measures and charts help visualize and quantify differences.

Question 11

Which of the following best describes the term 'data' in Informatics Practices?

Accepted Answer

A collection of characters, numbers, and symbols representing values of variables — Data is defined as a collection of characters, numbers, and other symbols that represent values of some situations or variables. It is raw and unprocessed, unlike information or knowledge.

Question 12

Assertion (A): Data and information are the same and can be used interchangeably.
Reason (R): Data is raw and unprocessed, while information is processed data that is meaningful.

Accepted Answer

D — Assertion is false because data and information are not the same; data is raw and unprocessed, whereas information is processed data that provides meaning. Reason is true and correctly explains the difference.

Question 13

Which of the following is NOT an example of data collected by governments through census?

Accepted Answer

Number of mobile phones sold in a city — Census data typically includes population, education, housing, etc. Number of mobile phones sold is commercial sales data, not part of census.

Question 14

Explain why data processing is essential before making decisions using data, with an example from the chapter.

Accepted Answer

Data processing is essential because raw data is often large and unorganized, making it difficult to interpret directly. Processing summarises and analyses the data to produce meaningful information. For example, a college placement cell processes placement data of 2000 students over 3 years to create a brochure with summaries and visuals that help in decision making. — Data processing converts raw data into understandable information by summarisation and analysis, enabling informed decisions. The college placement example illustrates this by showing how raw placement data is transformed into useful insights.

Question 15

Identify the correct singular form of the word 'data'.

Accepted Answer

Datum — The singular form of 'data' is 'datum'. 'Data' is plural.

Understanding Chapter Data

Understanding Chapter Data — Study Notes

5.1 INTRODUCTION TO DATA

5.1.1 Importance of Data

5.1.2 Types of Data

Practice Questions — Understanding Chapter Data

All 8 Chapters in Informatics Practices