Introduction to Data Analysis

INF-604: Data Analysis

Lecturer: Dr. Sothea HAS

About the course

• Objective: Equip you with essential Data Analysis skills to uncover insights from data and make informed decisions.

• Grading Criteria

Criteria	Percentage
Attendance	10%
Participation & quiz	30%
Midterm Exam	30%
Final Project & Presentation / Practical labs	30%

• Programming:

• Python
• R

• Jupyter Notebook, Google colab, Matplotlib, Seaborn

• Rmarkdown/Quarto, Posit cloud, Ggplot2, Tidyverse

Where to visit

• Canvas & Course webpage: https://hassothea.github.io/Data_Analysis_AUPP/

Just want to know you a bit 👇

Let’s see 🫣

Introduction to
Data Analysis (DA)

📋 Outline

• Motivation & Overview
  

• Type of Data Analysis
  

• Related Roles in Data Ecosystem
  

• Key part: Data Analysis Process
  

• The Importance of Data Analysis
  

• Applications of Data Analysis
  

Motivation

Motivation

Old Faithful dataset (\(272\) rows, \(2\) columns)

import pandas as pd                 # Import pandas package
import seaborn as sns               # Package for beautiful graphs
import matplotlib.pyplot as plt     # Graph management
sns.set(style="whitegrid")          # Set grid background
# path = "https://gist.githubusercontent.com/curran/4b59d1046d9e66f2787780ad51a1cd87/raw/9ec906b78a98cf300947a37b56cfe70d01183200/data.tsv"                       # The data can be found in this link
df0 = pd.read_csv(path0 + "/faithful.csv" )  # Import it into Python
df0.head(5)                        # Randomly select 4 points

	eruptions	waiting
0	3.600	79
1	1.800	54
2	3.333	74
3	2.283	62
4	4.533	85

plt.figure(figsize=(5,3.2))                          # Define figure size
sns.scatterplot(df0, x="waiting", y="eruptions")    # Create scatterplot
plt.title("Old Faithful data from Yellowstone National Park, US", fontsize=10)    # Title
plt.suptitle("Eruptions vs waiting times", fontsize=13, y=1)                 # Subtitle
plt.show()

• The longer the wait, the longer duration of the eruption.

Motivation

Marketing (\(200\) rows, \(4\) columns)

import pyreadr
import pandas as pd
df = pyreadr.read_r(path + "/marketing.rda")
df = df['marketing']
df.head(5)

	youtube	facebook	newspaper	sales
0	276.12	45.36	83.04	26.52
1	53.40	47.16	54.12	12.48
2	20.64	55.08	83.16	11.16
3	181.80	49.56	70.20	22.20
4	216.96	12.96	70.08	15.48

Motivation

Marketing (\(200\) rows, \(4\) columns)

df.head(5)

	youtube	facebook	newspaper	sales
0	276.12	45.36	83.04	26.52
1	53.40	47.16	54.12	12.48
2	20.64	55.08	83.16	11.16
3	181.80	49.56	70.20	22.20
4	216.96	12.96	70.08	15.48

import plotly.express as px
fig = px.scatter(df, x="youtube", y="sales", size_max=40)
fig.update_layout(title="Sales as a function of Youtube Ads",
                  width=550, height=380)

fig = px.scatter_3d(df, x="youtube", y="facebook", z="sales", size_max=40)
camera = dict(eye=dict(x=1, y=-1, z=1.2))
fig.update_layout(title="Sales as a function of Facebook and Youtube",
                  width=550, height=380,
                  scene_camera=camera)

fig = px.scatter_3d(df, x="youtube", y="facebook", z="sales", 
                    size="newspaper", color="newspaper",
                    size_max=40)
camera = dict(eye=dict(x=1, y=-1, z=1.2))
fig.update_layout(title="Sales as a function of all ads",
                  width=550, height=380,
                  scene_camera=camera)

• Objective: Leverage this data to boost sales.

Data Analysis Overview

• Simply put, it’s a process of treating raw data and making sense of it.

• It involves using:

  • Statistical methods: descriptive, test, regression analysis…
  • Analytics tools: Python, , Excel, Power BI…
  • Techniques to identify patterns and trends: Data modeling, machine learning algorithms…

• It helps businesses understand past performance, customer behavior, market trends and guides decision-making for future actions and more.

• Example: What’s the best ad strategy for boosting sales?

Types of Data Analysis

Types of Data Analysis

1. Descriptive Analysis

• Summarizes and provides insights into the past events.
• Answers to “What happened during that time?”
• Example: average expenses on ads, average sales…

Types of Data Analysis

2. Diagnostic Analysis

• Delves deeper into the reasons behind specific outcomes.
• Answers to “Why did it happen?”.
• Example: why did the sales decreased or increased?

Types of Data Analysis

3. Predictive Analysis

• Forecasts future outcomes using historical data and trends.
• Answers to “What’s likely to happen next?”.
• Example: how will the next ads impact sales?

Types of Data Analysis

4. Prescriptive Analysis

• Use estimated outcomes to guide appropriate actions.
• Answers to “What’s the best course of action to take?”.
• Example: what is the most effective ad strategy?

Related Roles

Related Roles in Data Ecosystem

1. Data Engineer

2. Data Analyst

3. Data Scientist

4. Machine Learning Engineer

5. Business Analyst and Business Intelligent (BI) Analyst

Related Roles in Data Ecosystem

1. Data Engineer

• Builds and maintains the infrastructure for data generation, collection, storage, and retrieval.
• Ensures efficient, scalable, and reliable data pipelines.
• Required skills:
  • ETL (Extract, Transform, Load)
  • Data warehousing, programming (Python, Java, SQL),
  • Big data technologies (Hadoop, Spark).

Related Roles in Data Ecosystem

2. Data Analyst

• Analyzes data to uncover trends and insights, providing actionable information to inform business decisions.
• Uses the data infrastructure set up by Data Engineers.
• Required skills:
  • Data cleaning, data visualization, statistical analysis.
  • Python, R, SQL, Excel.
  • Data visualization tools (Tableau, Power BI).

Related Roles in Data Ecosystem

3. Data Scientist

• Uses advanced analytics, including machine learning (ML) and predictive modeling, to solve complex problems and generate new insights.
• Builds on the work of Data Engineers and Data Analysts to create advanced models.
• Required skills:
  • ML algorithms, Deep learning.
  • Programming: Python, R.
  • Statistical analysis, data modeling.

Related Roles in Data Ecosystem

4. ML Engineer

• Develops, optimize, and maintains ML models and algorithms.
• Transforms prototypes into scalable and efficient model for real-world applications.
• Work closely with Data Scientists and Data Engineers.
• Required skills:
  • Programming: Python (TensorFlow, PyTorch), R, Java, etc.
  • Deep understanding of ML frameworks and algorithms.
  • Big data technologies, preprocessing, and feature engineering.

Related Roles in Data Ecosystem

5. Business & BI Analyst

• Improves business processes and strategies using data-driven insights.
• Focuses on creating dashboards and reports.
• Relies on data infrastructure and insights generated by Data Engineers, Data Analysts, and Data Scientists.
• Required skills:
  • Business process analysis
  • Data visualization,
  • SQL, Excel, BI tools (Tableau, Power BI).

Summary

Data Analyst vs Data Scientist

• Data analysis is central to the roles of both Data Analysts and Data Scientists.

Key parts of Data Analysis

Key parts of Data Analysis

1. Define the problem

• Define what is the problem? Desired outcomes?
• Define what metric may be used to measure its quality?
• Ex: What factors contribute to tourists’ happiness when visiting Angkor Wat?

Key parts of Data Analysis

2. Data Collection

• Identify necessary data and data sources.
• What tools to use? How should the data be organized?
  
• Ex: Where to collect the data? Platforms like TripAdvisor, Google Reviews, and social media, or Surveys?

Key parts of Data Analysis

3. Data Cleaning

• Address quality issues to ensure accurate analysis.
• Fix missing values, handle outliers, and standardize data…
• Ex: How should we store the data and clean it while preserving its quality and information?

Key parts of Data Analysis

4. Data Analyzing

• Manipulate data to identify trends, correlations, patterns…
• Examine the data and seek solutions to the problem.
• Ex: “What statistical values should we compute? Which graphs should we use? Which models should we try?

Key parts of Data Analysis

5. Interpretation

• Deduce key messages/findings from analysis results.
• Recognize the limitations of the analysis…
• Ex: What factors most influence tourists’ satisfaction? Answering our defined questions.

Key parts of Data Analysis

6. Visualization & presentation

• Present the findings using suitable graphs, charts, maps, etc.
• Convey the insights from the analysis effectively.
• Ex: How should we present our findings? Which values or graphs will help our audience easily understand?

The Importance of Data Analysis

The Importance of Data Analysis

• Analyzes past performance and uncovers trends, patterns, insights within data.
• Unables companies to make informed decisions.
• Leads to better strategies, optimized operations, and enhanced customer satisfaction.
• Saving time and resources.
• Drives innovation and fosters growth by identifying new opportunities and areas for improvement.

• This is the introduction of my PhD thesis:

Applications

Applications of Data Analysis

• Customer Insights: Understand behavior & preferences.
• Market Research: Spot trends and opportunities.
• Healthcare: Improve patient outcomes using clinical data.
• Supply Chain Management: Optimize inventory and logistics.
• Fraud Detection: Identify fraudulent activities.
• Marketing Campaigns: Personalize ads strategies.
• Human Resources: Analyze employee performance.
• Sales Forecasting: Predict future trends.

🥳 Yeahhhh….

Party time… 🥂