#### Business Modeling- t-Test

###### Statistics- Overview of t-Tests

A t-test is the most frequently used test in the field of statistics. It’s often used to determine the difference between population mean and sample mean or two sample means.

###### Statistics- One Sample t-Test

One sample t-test is use to find the variation between one sample mean and population mean.

###### Statistics- z- test vs t-Tests

#### Database Management Systems- Introduction to Joins

###### SQL Joins

A SQL join clause combines records from two or more tables in a relational database. There are 4 main kinds of JOIN statements- INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN. An overview of all the main JOINs is given in the following 2 videos. Don't worry if you don't understand all of it. We will cover each JOIN statement individually and give you enough practice to get used to it. Read a simple explanation after watching the videos below.