# Data Science for Beginners Part 2

*2021-06-25*

# Welcome to Data Scince

Department of Statistics

Faculty of STEM

Tangerang, Banten

Info: siregarbakti@gmail.com

## Preface

In this book, we will begin to the next level of data science (Beginners part 2). Here, we will focus on computational statistics. The first section, focus on the fundamental of elementary statistics. These topics have to be done before we begin to learn inferential statistics (Regression & ANOVA):

- Probability Distributions
- Confidence Intervals
- Hypothesis Testing
- A/B Testing
- Goodness of Fit
- Non-parametric Methods

The second section, we will learn one of the most important models in Regression Analysis:

- Simple Linear Regression
- Inference Linear Regression
- Multiple Linear Regression
- Logistic Regression

In the third section, we learn how to compare multiple means in R using the ANOVA (Analysis of Variance) method and variants, including:

**ANOVA test**for comparing independent measures.**Repeated-measures ANOVA**, which is used for analyzing data where the same subjects are measured more than once.**Mixed-ANOVA**, which is used to compare the means of groups cross-classified by at least two factors, where one factor is a “within-subjects” factor (repeated measures) and the other factor is a “between-subjects” factor.**ANCOVA**(Analyse of Covariance), an extension of the one-way ANOVA that incorporates a covariate variable.**MANOVA**(Multivariate Analysis of Variance), an ANOVA with two or more continuous outcome variables.

## About Me

I started using R in 2012 when I was a college undergraduate working on my homework in a course of Computational Statistics. The version was 2.15.1. I was an applied mathematics major with a statistics concentration. After college in October 2013, I enrolled in a Management Trainee (MT) at Sinar Mas Insurance as an Underwriter for about three months. Then move to a similar employee training process called Office Deployment Program (ODP) at MPM Finance as a Credit Analyst (about six months). After all of this experience, I realize that to upgrade my study to the next level because I was considered my self is not good enough to be successful in my carrier with limited knowledge. Therefore, while I followed the training process I always tried to apply to several foreign universities.

In September 2014, I was lucky to say I get the opportunity to continue my master’s degree at National Sun Yat-Sen University (Taiwan) on a scholarship program. In this university I registered in the department of applied mathematics with a statistics concentration. I learned a lot on this campus, starting from the perspective of life, culture, respect for others, always being on time, increasing my statistical knowledge, and so on. During my study, I was working with my professor as a teaching assistant and I was lucky to get an extra allowance. For that am focus on teaching, I have to attend our Lab meeting ones or twice a week, helping university events, organize some trip activities, and joint some research with (Prof. Mei-Hui Guo and Prof. Chung Chang). They advise me to learn at least the basics of Mandarin to survive in Taiwan and must be consistently improving my programming skills with R, Python, SAS, and MATLAB to handle all my homework as well.

In the next step of my career, I went to the department of engineering at PT Andalan Furnindo (Samora Group) as a data analyst. It’s one of the best Sugar Industry in Indonesia, where I have been for at least one year since 2017. Then I felt that not all of my knowledge could be used in this company, not even able to develop it at a better level. So with a great challenge, I decided to move to a new place that is Matana University in 2018, here I began to dedicate myself by teaching business statistics and continue to develop with new sciences. Here I learn a lot and teach about data science, I am focusing on teaching data structure and algorithm, database system, computational statistics, econometrics, time series, calculus, optimizations, research methods, etc. Above of all, I confident to say that I have an expert skill with some programming languages such as R, Python, SQL, etc, and also I have good enough ability to use Business Intelligence Tools, for instance, Tableau and SAS.

Bakti Siregar, M.Sc

Email: siregarbakti@gmail.com / siregar.bakti@matanauniversity.ac.id

Github: https://github.com/Bakti-Siregar

LinkedIn: https://www.linkedin.com/in/bakti-siregar-15955480/