Introduction

What is Data Science?

Data Science is about storytelling and making sense of numbers.

A good preliminary step of most analyses is to visual the data and examine it.

We can gain insights from larger data sets with various algorithms so we can turn all types of data into actionable insights.

Basically :

Typing Codes
Create a Dendrogram
Analyzing a heatmap
Finding the optimal number of clusters

Skillset needed

Intro to data and data science
Math
Statistics / Advanced statistics
Python
Machine Learning

Keywords of Data Science

Data - The data used for analytic
Algorithm - The tool you used for analytic
Insight - The observation

Various Data Science Disciplines

The data science team will use some business analytics or data analytics tools to develop models that could predict future outcomes.

History

Statistician (25 years ago)

Statistic

Responsible for :

gathering and cleaning data sets
appling statistical methods

+Growth of data

+radical improvement of technology
extracting patterns from data

Data mining specialist (20 years ago)

Data mining

Responsible for :

gathering and cleaning data sets
appling statistical methods

+Growth of data

+radical improvement of technology
extracting patterns from data

+new models
performing more accurate forecasts

Predictive analytics specialist (10 years ago)

Predictive analytics

Responsible for :

gathering and cleaning data sets
appling statistical methods
extracting patterns from data
performing more accurate forecasts

Data Scientist (Now)

Data Science

Responsible for :

gathering and cleaning data sets
appling statistical methods
extracting patterns from data
performing more accurate forecasts

Difference Between Analysis and Analytics

Analysis

Separate dataset into chunks and study them individually and examine how they relate to other parts.
Analyses on things in the PAST (already happened things)
To Explain How and Why

Qualitative Analysis

intuition + analysis (e.g. BI)

Quantitative Analysis

formulas + algorithms (e.g. SWOT)

Analytics

Explores potential FUTURE
the application of logical and computational reasoning to the component parts obtained in an analysis
Looking for patterns in exploring what you can do with them in the future

Qualitative Analytics

intuition + analysis

Quantitative Analytics

formulas + algorithms

Business Analytics, Data Analytics and Data Science

not a strict representation

Left = Analysis, Right = Analytics

The above graph just to help you understand it better. No need to remember this.

Some terms explained

Data Science

A discipline reliant on data availability, while business analytics does not completely rely on data
can be used to improve the accuracy of predictions based on data extracted from various activities typical for drilling efficiency.
Tools include : Statistical, mathematical, programming, problem-solving, data-management

Digital signal

used to represent data in the form of discrete values which is an example of numeric data
data analytics can be applied to digital signal in order to produce a higher quality signal

Preliminary data report

first step of any data analysis

Artificial intelligence (AI)

simulating human knowledge and decision making with computers

Symbolic reasoning

based on high-level human-readable representation of problems and logic
- Speech recognition
- Image recognition

Connecting the Data Science Disciplines

When and Why - keyword explained

Data

Information stored in a digital format which can then be used as a base for performing analyses and decision making.

Traditional data

In the form of tables containing numeric or text values data
Structured and stored in databases
Can be managed from one computer

Big Data

Extremely large data
can be structured, semi-structured or unstructured
3V of big data
- Volume - Require a huge amount of memory space distribbuted between many computers
- Variety - Dealing not only numbers and text, but also images, audio, mobile datas
- Velocity - Result could be computed immediately after the source data has been obtained

Data Science

Business Intelligence (BI)

the process of analysing and reporting historical business data
aims to explain past events using business data
Preliminary step of predictive analytics
For marking decisions, extracting insights, extracting ideas

Traditional methods

Perfect for forecasting future performance with great accuracy
Analysis include:

Machine Learning (ML)

The ability of machines to predict outcomes without being explicitly programmed to
creating and implementing algorithms that let machines receive data and use this data to:
- make predictions
- analyse patterns
- Give recommendations
Cannot be implemented without data

What and Where - keyword explained

Tradional Data - What

Data Gathering

Manual - e.g. Surveys
Automatic - e.g. Cookies

Data Pre-Processing

Such data must be marked as invalid or corrected
Class labeling - data point to correct data type or arranging data by category
Data cleansing - deal with inconsistent data (e.g. spell check)
Dealing with missing values

Case Specific

Balancing
Shuffing datasets - prevents unwanted patterns and improves predictive performance
E.R diagram (Entity-relationship diagram)
Relational Schema

Big Data - What

Case Specific

Text data mining - the process of deriving valuable unstructured data from a text
Data Masking
- analyse the information without compromising private details
- conceals the original data with random and false data
- conduct analysis
- keep all confidential information in a secure place

Business Intelligence - What

Analyze The Data

metrics - aims at guaging business performance or progress
KPI (Key Performance Indicators) - a metric that is tightly aligned with your business objectives

Traditional Methods

Linear Regression

a model used for quantifying causal relationships among the different variables included in your analysis

Regression Line $y = bx$ where b is co

Logistic Regression

the values on the vertical line will be 1s and 0s only

Cluster Analysis

Grouping observations together

Time Series

To visualize thing performed well or not by ploting values against time.

Mechine Learning - What

Data -> Model -> Objective Function -> Optimization Algorithm

To Better Illustrate:

Types of Mechine Learning

Supervised Learning - training an algorithm resembles a teacher supervising her students (work with labelled data)

SVMs (support vector machines)
NNs (Neural Networks)
Deep Learning

Unsupervised Learning - no targets, no supervising (save time) (work with unlabelled data)

K-means
Deep Learning

Reinforcement Learning - with a reward system to maximize the objective function

Deep Learning

How - keyword explained

Programming Languages

Python and R

suitable for mathematical and statistical computations
adaptable
not able to address problems specific to some domains, e.g. relational database management systems

SQL

working with relational database management systems

MATLAB

working with mathematical functions or matix manupulations
it is a paid service

Java and Scala

Useful when combining data from multiple sources (Big Data)

Software / Software Framework

Excel

able to do relatively complex computations and good visualizations quickly

SPSS

famous for working with traditional data and applying statistical analysis

MongoDB and hadoop

designed for working with big data

Power BI , SAS, Qlik and Tableau

designed for business intelligence visualizations in terms of predictive analytics use

EViews

working with econometric time-series models

Stata

for academic statistical and econometric research

Careers in Data Science

Data - Careers

Data Architect
- designs the way data will be retrieved, processed and consumed
Data Engineer
- processes the obtained data so that it is ready for analysis
Database Administrator
- handles this control of data and works with traditional data

Business Intelligence - Careers

BI Analyst
- performs analyse and reporting of past historical data
BI Consultant
- external BI analyst
BI developer
- perform analyses specifically designed for the company with python and sql

Mechine Learning - Careers

Data Scientist
- employs traditional statistical methods or unconventional machine learning techniques for making predictions
Data Analyst
- prepares more advanced types of analyses
ML Engineer
- applies state-of-the-art computational models

Reference

The Data Science Course 2020: Complete Data Science Bootcamp