Often when you get a dataset, it is not in the exact format you want$/$need$.$ So$,$ you have to refine the dataset into something more useful $$ this is often called $$data munging.$$ In this lab exercise, you will read in a dataset and work on that $($in a dataframe$).$ Then, you will explore the distribution within the dataset.

An interactive tutorial on basic to advanced R features is also available within R itself. It is called Statistics With Interactive R Learning $($SWIRL$).$ More information about installing and using this feature can be found at http:$//$swirlstats$.$com$/$students$.$html

Review the Readings$/$Resources in the unit. Complete the following steps:

Create a function $($named readStates$)$ to read a CSV file into R

You need to read a URL, not a local file to your computer.

The file is a dataset on state populations $($within the United States$)$

The URL is:https:$//$www$2.$census.gov$/$programs$-$surveys$/$popest$/$tables$/2010-2011/$state$/$totals$/$nst$-$est$2011-01.$csv $($Note that you might need to use https:$//$ rather than http:$//)$

Clean the dataframe

Note the issues that need to be fixed $($removing columns, removing rows, changing column names$).$

Within your function, make sure there are $51$ rows $($one per state $+$ the district of Columbia$).$

Make sure there are only $5$ columns with the columns having the following names $($stateName$,$ Census, Estimates, Pop$2010,$ Pop$2011).$

Make sure the last four columns are numbers $($i$.$e$.$ not strings$).$

Store and explore the dataset

Store the dataset into a dataframe, called dfStates.

Test your dataframe by calculating the mean for the $2011$ data, by doing: mean$($dfStates$Pop$2011).$

Find the state with the highest population

Based on the $2011$ data, what is the population of the state with the highest population? What is the name of that state?

Sort the data, in increasing order, based on the $2011$ data.

Explore the distribution of the states

Write a function that takes two parameters. The first is a vector and the second is a number.

The function will return the percentage of elements within the vector that is less than the same $($i$.$e$.$ cumulative distribution below the value provided$).$ For example, if the vector had $5$ elements $(1,2,3,4,5),$ with $2$ being the number passed into the function, the function would return $0\mathrm{.}2($since $20\%$ of the numbers were below $2).$

Test the function with the vector $$dfStates$Pop$2011,$ and the mean of $$dfStates$Pop$2011$