2: Exploratory Data Analysis

Exploratory Data Analysis

a statistical approach used to analyze datasets to summarize their main characteristics, often using visual methods. It helps in understanding the data's structure and any underlying patterns

Data wrangling

the process of cleaning and transforming raw data into a usable format. It includes handling missing values, correcting inconsistencies, and structuring data for analysis

%in%

a logical operator in R that checks if elements of one vector are contained in another vector, returning TRUE or FALSE for each comparison

is.na()

a function in R used to identify missing values in a vector or data frame. It returns a logical vector indicating which elements are NA (not available)

!is.na()

a function in R that returns a logical vector indicating which elements are not missing (i.e., not NA) in a vector or data frame

filter()

a function in R used to subset a data frame or tibble based on specified conditions, returning only the rows that meet those criteria

select()

a function in R used to subset columns from a data frame based on specified conditions, allowing for the extraction of specific variables

starts_with()

a function in R that selects columns whose names begin with a specified prefix, making it easier to grab multiple columns at once based on their naming convention

ends_with()

a function in R that selects columns whose names end with a specified suffix, allowing users to efficiently gather variables based on their naming

contains()

a function in R that selects columns containing a specified substring within their names, facilitating the extraction of relevant variables regardless of their position in the name

mutate()

a function in R that allows you to edit existing columns or create new columns in an existing data frame, and you can perform calculations on existing columns to return outputs in the new column

if_else()

a function in R that allows for vectorized conditional statements, returning one value when a condition is true and another when it is false, simplifying data transformation and manipulation

paste()

a function in R used to concatenate strings together, allowing for flexible combination of text and variables for creating new character vectors

group_by()

a function in R used to specify that operations should be performed by groups within a data frame, facilitating grouped calculations and summarizations

summarise()

a function in R that reduces a data frame to summary statistics for each group, often used in conjunction with group_by() to provide concise data insights

geom_histogram()

a function in R used to create histogram visualizations

fill =

an aesthetic mapping in ggplot2 that determines the fill color of plotted elements based on a specified variable

scale_fill_manual()

a function in ggplot2 that allows manual specification of fill colors for different levels of a categorical variable, enhancing customization in visualizations

facet_wrap()

a function in ggplot2 used to create a series of plots arranged in a grid, based on the values of one or more categorical variables, allowing for easy comparison across groups