7 Essential Data Analysis Techniques You Need to Know in 2025

✅ Exploratory Data Analysis (EDA) – Uncover patterns, spot anomalies, and visualize distributions before diving deeper
✅ Time Series Analysis – Analyze trends over time, forecast future values (using ARIMA or Prophet)
✅ Hypothesis Testing – Use statistical tests (T-tests, Chi-square) to validate assumptions and claims
✅ Regression Analysis – Predict continuous variables using linear or non-linear models
✅ Cluster Analysis – Group similar data points using K-means or hierarchical clustering
✅ Dimensionality Reduction – Simplify complex datasets using PCA (Principal Component Analysis)
✅ Classification Algorithms – Predict categorical outcomes with decision trees, random forests, and SVMs

Mastering these will give you the edge in any data analysis role.

Free Resources: https://whatsapp.com/channel/0029VaGgzAk72WTmQFERKh02

Excel vs SQL vs Python (pandas):

1️⃣ Filtering Data
↳ Excel: =FILTER(A2:D100, B2:B100>50) (Excel 365 users)
↳ SQL: SELECT * FROM table WHERE column > 50;
↳ Python: df_filtered = df[df['column'] > 50]

2️⃣ Sorting Data
↳ Excel: Data → Sort (or =SORT(A2:A100, 1, TRUE))
↳ SQL: SELECT * FROM table ORDER BY column ASC;
↳ Python: df_sorted = df.sort_values(by="column")

3️⃣ Counting Rows
↳ Excel: =COUNTA(A:A)
↳ SQL: SELECT COUNT(*) FROM table;
↳ Python: row_count = len(df)

4️⃣ Removing Duplicates
↳ Excel: Data → Remove Duplicates
↳ SQL: SELECT DISTINCT * FROM table;
↳ Python: df_unique = df.drop_duplicates()

5️⃣ Joining Tables
↳ Excel: Power Query → Merge Queries (or VLOOKUP/XLOOKUP)
↳ SQL: SELECT * FROM table1 JOIN table2 ON table1.id = table2.id;
↳ Python: df_merged = pd.merge(df1, df2, on="id")

6️⃣ Ranking Data
↳ Excel: =RANK.EQ(A2, $A$2:$A$100)
↳ SQL: SELECT column, RANK() OVER (ORDER BY column DESC) AS rank FROM table;
↳ Python: df["rank"] = df["column"].rank(method="min", ascending=False)

7️⃣ Moving Average Calculation
↳ Excel: =AVERAGE(B2:B4) (manually for rolling window)
↳ SQL: SELECT date, AVG(value) OVER (ORDER BY date ROWS BETWEEN 2 PRECEDING AND CURRENT ROW) AS moving_avg FROM table;
↳ Python: df["moving_avg"] = df["value"].rolling(window=3).mean()

8️⃣ Running Total
↳ Excel: =SUM($B$2:B2) (drag down)
↳ SQL: SELECT date, SUM(value) OVER (ORDER BY date) AS running_total FROM table;
↳ Python: df["running_total"] = df["value"].cumsum()

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I’m a data analyst

2022:

. Got my first analyst job
. Never used PowerBi
. Only knew Pivot tables
. Didn’t really understand SQL

2025:

. 2 years data consulting
. Lead analyst for $100m project
. Love my job and look forward to Mondays

A lot can change in 3 years - Never Give Up.

For data analysts working with Python, mastering these top 10 concepts is essential:

1. Data Structures: Understand fundamental data structures like lists, dictionaries, tuples, and sets, as well as libraries like NumPy and Pandas for more advanced data manipulation.

2. Data Cleaning and Preprocessing: Learn techniques for cleaning and preprocessing data, including handling missing values, removing duplicates, and standardizing data formats.

3. Exploratory Data Analysis (EDA): Use libraries like Pandas, Matplotlib, and Seaborn to perform EDA, visualize data distributions, identify patterns, and explore relationships between variables.

4. Data Visualization: Master visualization libraries such as Matplotlib, Seaborn, and Plotly to create various plots and charts for effective data communication and storytelling.

5. Statistical Analysis: Gain proficiency in statistical concepts and methods for analyzing data distributions, conducting hypothesis tests, and deriving insights from data.

6. Machine Learning Basics: Familiarize yourself with machine learning algorithms and techniques for regression, classification, clustering, and dimensionality reduction using libraries like Scikit-learn.

7. Data Manipulation with Pandas: Learn advanced data manipulation techniques using Pandas, including merging, grouping, pivoting, and reshaping datasets.

8. Data Wrangling with Regular Expressions: Understand how to use regular expressions (regex) in Python to extract, clean, and manipulate text data efficiently.

9. SQL and Database Integration: Acquire basic SQL skills for querying databases directly from Python using libraries like SQLAlchemy or integrating with databases such as SQLite or MySQL.

10. Web Scraping and API Integration: Explore methods for retrieving data from websites using web scraping libraries like BeautifulSoup or interacting with APIs to access and analyze data from various sources.

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Want to make a transition to a career in data?

Here is a 7-step plan for each data role

Data Scientist

Statistics and Math: Advanced statistics, linear algebra, calculus.
Machine Learning: Supervised and unsupervised learning algorithms.
xData Wrangling: Cleaning and transforming datasets.
Big Data: Hadoop, Spark, SQL/NoSQL databases.
Data Visualization: Matplotlib, Seaborn, D3.js.
Domain Knowledge: Industry-specific data science applications.

Data Analyst

Data Visualization: Tableau, Power BI, Excel for visualizations.
SQL: Querying and managing databases.
Statistics: Basic statistical analysis and probability.
Excel: Data manipulation and analysis.
Python/R: Programming for data analysis.
Data Cleaning: Techniques for data preprocessing.
Business Acumen: Understanding business context for insights.

Data Engineer

SQL/NoSQL Databases: MySQL, PostgreSQL, MongoDB, Cassandra.
ETL Tools: Apache NiFi, Talend, Informatica.
Big Data: Hadoop, Spark, Kafka.
Programming: Python, Java, Scala.
Data Warehousing: Redshift, BigQuery, Snowflake.
Cloud Platforms: AWS, GCP, Azure.
Data Modeling: Designing and implementing data models.

#data

📖 Starter Kit 2025 - Data Analyst

9 secrets about Data Storytelling every analyst should know (number 6 is a must):

1/ Start with the end in mind—what’s the key takeaway?

2/ Don’t just present numbers—explain the 'so what' behind them.

3/ Data should drive decisions—frame your analysis as a solution to a problem.

#DataAnalytics

4/ Visualise trends over time to tell a story.

5/ Add context to your data—it makes your insights relevant.

6/ Speak the language of your audience—simplify complex terms.

7/ Use metaphors or analogies to explain difficult concepts. Don't use professional jargon.

8/ Include both the big picture and the details—it appeals to different stakeholders.

9/ Conclude with a call to action—what should they do next?

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Data Analysis vs Data Science

Data analysis often focuses on interpreting and summarizing existing data, requiring skills like statistical analysis, SQL, and data visualization.
On the other hand, data science involves a broader set of skills, including machine learning, predictive modeling, and advanced programming.

In essence, data analysis is a subset of data science, with data scientists often having a more extensive toolkit for handling complex and unstructured data.

Free Resources to become data analyst -> https://www.linkedin.com/posts/sql-analysts_freecertificates-dataanalysts-python-activity-7113004712412524545-Uw4k

Steps to become data scientist -> https://t.iss.one/learndataanalysis/559

TOP CONCEPTS FOR INTERVIEW PREPARATION!!

🚀TOP 10 SQL Concepts for Job Interview

1. Aggregate Functions (SUM/AVG)
2. Group By and Order By
3. JOINs (Inner/Left/Right)
4. Union and Union All
5. Date and Time processing
6. String processing
7. Window Functions (Partition by)
8. Subquery
9. View and Index
10. Common Table Expression (CTE)


🚀TOP 10 Statistics Concepts for Job Interview

1. Sampling
2. Experiments (A/B tests)
3. Descriptive Statistics
4. p-value
5. Probability Distributions
6. t-test
7. ANOVA
8. Correlation
9. Linear Regression
10. Logistics Regression


🚀TOP 10 Python Concepts for Job Interview

1. Reading data from file/table
2. Writing data to file/table
3. Data Types
4. Function
5. Data Preprocessing (numpy/pandas)
6. Data Visualisation (Matplotlib/seaborn/bokeh)
7. Machine Learning (sklearn)
8. Deep Learning (Tensorflow/Keras/PyTorch)
9. Distributed Processing (PySpark)
10. Functional and Object Oriented Programming

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Steps to become data analyst when you are fresher 👇👇

1 - First try to focus 3 mandatory skills i.e. Sql, Ms excel and python -

- For sql you can refer Ankit Bansal Or Thoufiq Mohammed (techtfq) on @sqlanalyst
- For Ms excel refer Leila Gharani or @excel_analyst
- For python refer freecodecamp from YouTube or @pythonanalyst

2 - After that try to be clear with basic idea of tableau or powerbi. (Not mandatory for every job). You can refer this channel for free resources https://t.iss.one/PowerBI_analyst

3 - Add your college project in your resume, if it's a data science related project it will help a lot. If you don't have project then you can make some dashboarding projects from YouTube in tableau/powerbi.

4 - And start applying for jobs which is having 0-1 yr experience required, you can also apply for 1 yr experience required job in analytics because sometimes they may consider fresher also. You can refer this channel @jobs_sql for job opportunities

Data types are foundational in computing, and it's essential to understand them to work effectively in any programming environment.

Let's take a dive into the top ten commonly used data types:

1. Integer (int):
- Represents whole numbers.
- Examples: -2, -1, 0, 1, 2, 3

2. Floating Point (float/double):
- Represents numbers with decimals.
- Examples: -2.5, 0.0, 3.14

3. Character (char):
- Represents single characters.
- Examples: 'A', 'b', '1', '%'

4. String:
- Represents sequences of characters, basically text.
- Examples: "Hello", "ChatGPT", "1234"

5. Boolean (bool):
- Represents true or false values.
- Examples: True, False

6. Array:
- Represents a collection of elements, often of the same type.
- Examples: [1, 2, 3], ["apple", "banana", "cherry"]

7. Object:
- Used in object-oriented programming, represents a combination of data and methods to manipulate the data.
- Examples: A Car object might have data like color and speed and methods like drive() and park().

8. Date & Time:
- Represents date and time values.
- Examples: 23-10-2023, 12:30:45

9. Byte & Binary:
- Represents raw binary data.
- Examples: 01010101 (Byte), 101000111011 (Binary)

10. Enum:
- Represents a set of named constants.
- Examples: Days of the week (Monday, Tuesday...), Colors (Red, Blue, Green)

Choosing the Right Chart Type

Selecting the appropriate chart can make or break your data storytelling. Here's a quick guide to help you choose the perfect visualization:

↳ 𝐁𝐚𝐫 𝐂𝐡𝐚𝐫𝐭𝐬: Perfect for comparing quantities across categories (Think: regional sales comparison)

↳ 𝐋𝐢𝐧𝐞 𝐂𝐡𝐚𝐫𝐭𝐬: Ideal for showing trends and changes over time (Example: monthly website traffic)

↳ 𝐏𝐢𝐞 𝐂𝐡𝐚𝐫𝐭𝐬: Best for showing parts of a whole as percentages (Use case: market share breakdown)

↳ 𝐇𝐢𝐬𝐭𝐨𝐠𝐫𝐚𝐦𝐬: Great for showing the distribution of continuous data (Like salary ranges across your organization)

↳ 𝐒𝐜𝐚𝐭𝐭𝐞𝐫 𝐏𝐥𝐨𝐭𝐬: Essential for exploring relationships between variables (Perfect for marketing spend vs. sales analysis)

↳ 𝐇𝐞𝐚𝐭 𝐌𝐚𝐩𝐬: Excellent for showing data density with color variation (Think: website traffic patterns by hour/day)

↳ 𝐁𝐨𝐱 𝐏𝐥𝐨𝐭𝐬: Invaluable for displaying data variability and outliers (Great for analyzing performance metrics)

↳ 𝐀𝐫𝐞𝐚 𝐂𝐡𝐚𝐫𝐭𝐬: Shows cumulative totals over time (Example: sales growth across product lines)

↳ 𝐁𝐮𝐛𝐛𝐥𝐞 𝐂𝐡𝐚𝐫𝐭𝐬: Powerful for displaying three dimensions of data (Combines size, position, and grouping)

𝐏𝐫𝐨 𝐓𝐢𝐩: Always consider your audience and the story you want to tell when choosing your visualization type.

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Want to practice for your next interview?

Then use this prompt and ask Chat GPT to act as an interviewer 😄👇 (Tap to copy)

I want you to act as an interviewer. I will be the
candidate and you will ask me the
interview questions for the position position. I
want you to only reply as the interviewer.
Do not write all the conservation at once. I
want you to only do the interview with me.
Ask me the questions and wait for my answers.
Do not write explanations. Ask me the
questions one by one like an interviewer does
and wait for my answers. My first
sentence is "Hi"

Now see how it goes. All the best for your preparation
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🌮 Data Analyst Vs Data Engineer Vs Data Scientist 🌮


Skills required to become data analyst
👉 Advanced Excel, Oracle/SQL
👉 Python/R

Skills required to become data engineer
👉 Python/ Java.
👉 SQL, NoSQL technologies like Cassandra or MongoDB
👉 Big data technologies like Hadoop, Hive/ Pig/ Spark

Skills required to become data Scientist
👉 In-depth knowledge of tools like R/ Python/ SAS.
👉 Well versed in various machine learning algorithms like scikit-learn, karas and tensorflow
👉 SQL and NoSQL

Bonus skill required: Data Visualization (PowerBI/ Tableau) & Statistics

Free Resources 👇

Data Science: https://whatsapp.com/channel/0029Va8v3eo1NCrQfGMseL2D

Data Analyst: https://whatsapp.com/channel/0029VaGgzAk72WTmQFERKh02

Data Engineers: https://whatsapp.com/channel/0029Vaovs0ZKbYMKXvKRYi3C

Here are 5 key Python libraries/ concepts that are particularly important for data analysts:

1. Pandas: Pandas is a powerful library for data manipulation and analysis in Python. It provides data structures like DataFrames and Series that make it easy to work with structured data. Pandas offers functions for reading and writing data, cleaning and transforming data, and performing data analysis tasks like filtering, grouping, and aggregating.

2. NumPy: NumPy is a fundamental package for scientific computing in Python. It provides support for large, multi-dimensional arrays and matrices, along with a collection of mathematical functions to operate on these arrays efficiently. NumPy is often used in conjunction with Pandas for numerical computations and data manipulation.

3. Matplotlib and Seaborn: Matplotlib is a popular plotting library in Python that allows you to create a wide variety of static, interactive, and animated visualizations. Seaborn is built on top of Matplotlib and provides a higher-level interface for creating attractive and informative statistical graphics. These libraries are essential for data visualization in data analysis projects.

4. Scikit-learn: Scikit-learn is a machine learning library in Python that provides simple and efficient tools for data mining and data analysis tasks. It includes a wide range of algorithms for classification, regression, clustering, dimensionality reduction, and more. Scikit-learn also offers tools for model evaluation, hyperparameter tuning, and model selection.

5. Data Cleaning and Preprocessing: Data cleaning and preprocessing are crucial steps in any data analysis project. Python offers libraries like Pandas and NumPy for handling missing values, removing duplicates, standardizing data types, scaling numerical features, encoding categorical variables, and more. Understanding how to clean and preprocess data effectively is essential for accurate analysis and modeling.

By mastering these Python concepts and libraries, data analysts can efficiently manipulate and analyze data, create insightful visualizations, apply machine learning techniques, and derive valuable insights from their datasets.

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ENJOY LEARNING 👍👍