# Big Data: Meet PCA

## Understanding Principal Component Analysis

What is an unsupervised learning algorithm?

Before we dive into Principal Component Analysis, we need to understand what an unsupervised learning algorithm is. Unsupervised learning does not have a target variable, whereas supervised learning does. Unsupervised machine learning algorithms look to identify some underlying patterns within the data. If there is no target we are predicting, how do we know that the groups we are picking are good? This is one of the biggest challenges of unsupervised machine learning. This is very subjective, so we cannot say for sure if they are good. …

# Overview of Logistic Regression:

In my last article, we dove into the purpose and methodology of linear/multiple linear regression analysis. Linear regression analysis is used when you want to predict a continuous dependent (y, response) variable using a number of independent (x, explanatory) variables.

But what happens when you want to predict a categorical outcome using a linear model? You might run into some trouble because a continuous variable outcome will be much harder to interpret (and most likely will not make sense). In fact, we will need to use a different model in order to predict our categorical response variable. How can we…

# Understanding Multiple Linear Regression

A Guide for Beginners

Why do we use multiple linear regression?

Multiple linear regression is the most common and most important form of regression analysis and is used to predict the outcome of a variable based on two or more independent (or explanatory) variables. Why? By using multiple regression, we can see what the relative influence of one variable is on another. For instance, we can see if the number of bathrooms in a house affects price, holding all else equal. If we only have one variable affecting our dependent variable (housing prices), we would be creating a simple linear…

# If not now, when? Why I Chose to Invest in Myself: A Data Science Odyssey

“If not now, when?”, a statement I have heard from my family, friends and mentors since I was young. The question of “why not now” has always troubled me, especially when confronted with big decisions. The idea of not taking action because of some internal/external reason (i.e. you are anxious, afraid, or in the middle of a pandemic) often feels like a weak excuse, rather than a valid justification. I find myself asking: Is it because I am afraid? Is it because I am content or complacent? The question “Why not now” feels like a challenge: If I am not… ## Christa Dawson

A budding data scientist!