# Basic statistics concepts

In this recipe, you will learn about the `StatsBase`

package, which helps you use basic statistical concepts such as weight vectors, common statistical estimates, distributions, and others.

## Getting ready

To get started with this recipe, you have to first install the `StatsBase`

package by executing `Pkg.add("StatsBase")`

in the REPL.

## How to do it...

- Weight vectors can be constructed as follows:
**w = WeightVec([4., 5., 6.])** - Weight vectors also compute the sum of the weights automatically. So, if the sum is already computed, it can be added as a second argument to the vector construction so that it saves time required for computing the sum. Here is how to do it:
**w = WeightVec([4., 5., 6.], 15.)** - Weights can also be simply defined by the
`weights()`

function, as follows:**w = weights([1., 2., 3.])** - Some important methods that can be used on weight vectors are:
- To check whether the weight vector is empty or not, the
`isemply()`

function can be used:**isempty...**

- To check whether the weight vector is empty or not, the