Statistics: Descriptive vs Inferential, Population vs Sample (Notes)

Continuing on with my Data Analytics learnings, with a jump into Descriptive Statistics vs Inferential Statistics and an attempt to clear up Population vs Sample from my last blog post. Descriptive Statistics Descriptive statistics takes a sample, e.g. a group and records data about that sample. The data is then presented in summary statistics and … Continue reading Statistics: Descriptive vs Inferential, Population vs Sample (Notes)

Data Variability: Standard Deviation and Variance (Notes)

When discussing data variability (i.e. how much the values vary) there are two methods that can help. These are Sample Standard Deviation and Sample Variance. Other Terms That Are Needed Measures of Centre The middle or centre of the data. Measures of Spread How diverse from the Measure of Centre data is, or how concentrated … Continue reading Data Variability: Standard Deviation and Variance (Notes)

SQL vs NoSQL (Notes)

A quick overview of the differences between SQL and NoSQL. SQL Structured Query Language (SQL) is used for relational databases, which are table based. For example, an column in table A (e.g. User_ID) may have a relation with a column in table B (e.g. Order_Ref) and table B may have a relation to a column … Continue reading SQL vs NoSQL (Notes)