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A scatter plot is a type of graph that helps you understand the relationship between two variables. Each dot on the plot represents one observation in your data — showing one value on the X-axis and another on the Y-axis.

By looking at the pattern of the dots, you can quickly see whether the two variables are related in any way.

Data normalization is the process of adjusting values in a dataset so they are on a common scale, without distorting differences in the data. It’s especially important when you’re comparing values that are measured in different units or have very different ranges.

In simple terms, normalization helps “level the playing field” so different variables can be compared fairly.

🔍 Why Is Data Normalization Important?

1. Ensures Fair Comparisons
 When data comes from different sources or scales (e.g., income in dollars and age in years), normalization makes it possible to compare them accurately.

2. Improves Accuracy in Analysis
 Many statistical and machine learning models perform better when data is normalized, especially those based on distance (like k-means clustering or nearest neighbor algorithms).

3. Reduces Bias from Extreme Values
 Normalization helps minimize the influence of large or small values that could otherwise skew your results.

4. Makes Visualizations Clearer
 Normalized data often leads to better graphs and charts by preventing one variable from overshadowing others.

🔢 Common Normalization Methods:

1. Min-Max Scaling
 Scales data to a range between 0 and 1.
 Formula: (Value – Min) ÷ (Max – Min)

2. Z-score Normalization (Standardization)
 Centers data around the mean with a standard deviation of 1.
 Formula: (Value – Mean) ÷ Standard Deviation

Analyzing survey or questionnaire data means turning raw responses into meaningful insights. The goal is to understand what your audience thinks, feels, or experiences based on their answers.

There are two main types of survey data:

- Quantitative data: Numerical responses (e.g., ratings, multiple-choice answers)
- Qualitative data: Open-ended, written responses (e.g., comments, opinions)

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🔍 How to Analyze Survey Data:

1. Clean the Data
 Remove incomplete or inconsistent responses. Make sure all data is accurate and usable.

2. Categorize the Questions
 Separate your questions into types:
– Yes/No or Multiple Choice (Closed-ended)
 - Rating Scales (e.g., 1 to 5)
 - Open-Ended (Written answers)

3. Use Descriptive Statistics
 For closed-ended questions:
– Count how many people chose each option
 - Calculate percentages, averages, and medians
 - Use charts like bar graphs or pie charts to visualize trends

4. Look for Patterns and Trends
 Compare responses between different groups (e.g., by age, location, or gender)
 Identify common opinions or issues that many people mentioned

5. Analyze Open-Ended Responses
 Group similar comments into categories or themes
 Highlight key quotes that illustrate major concerns or ideas

6. Draw Conclusions
 What do the results tell you?
 What actions can be taken based on the responses?
 Are there surprises or areas for improvement?

A pie chart is a circular graph used to show how a whole is divided into different parts. Each “slice” of the pie represents a category, and its size reflects that category’s proportion or percentage of the total.

It’s one of the simplest and most visual ways to display data — especially when comparing parts of a whole.

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🎯 Key Features of a Pie Chart:

• The entire circle represents 100% of the data.

• Each slice represents a specific category or group.

• Larger slices mean higher values or proportions.

• Often color-coded and labeled for clarity.

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🔍 How to Extract Insights from a Pie Chart:

1. Read the Title & Labels
 Start by understanding what the chart is showing — it could be market share, survey responses, budget breakdowns, etc.

2. Look at Slice Sizes
 Compare slice sizes to see which categories are biggest or smallest.
 The largest slice shows the most dominant group.

3. Check Percentages or Values
 If percentages or numbers are given, use them to understand how much each slice contributes to the whole.

4. Group Related Slices (if needed)
 Sometimes combining smaller slices can help identify trends (e.g., combining all “Other” categories).

5. Ask Questions Like:
 - Which category has the largest share?
 - Are any categories equal in size?
 - How balanced is the distribution?

Percentages and ratios are simple but powerful tools for understanding and comparing data. They help you express relationships between numbers in a way that’s easy to read, compare, and communicate.

Both are commonly used in business reports, surveys, research, and everyday decision-making.

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🔢 How to Calculate Percentages:

A percentage shows how much one value is out of 100.

👉 Formula:
Percentage = (Part ÷ Total) × 100

📊 Example:
If 40 out of 200 customers gave a 5-star review:
(40 ÷ 200) × 100 = 20%
So, 20% of customers gave top ratings.

✅ Interpreting It:
You can now say, “20% of our customers were highly satisfied.”

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📏 How to Calculate Ratios:

A ratio compares two quantities directly, showing how many times one value contains or relates to another.

👉 Formula:
Ratio = Value A : Value B