Imputation: Imputing missing values through linear regression
In rjaneUCF/MultiHazard-R-Package: Tools for modeling compound events

Description Usage Arguments Value Examples

Fits a simple linear regression model, impute missing values of the dependent variable.

1	Imputation(Data, Variable, x_lab, y_lab)

`Data`	Data frame containing two at least partially concurrent time series. First column may be a `"Date"` object. Can be `Dataframe_Combine` output.
`Variable`	Character vector of length one specifying the (column) name of the variable to be imputed i.e. dependent variable in the fitted regression.
`x_lab`	Character vector of length one specifying the name of the independent variable to appear as the x-axis label on a plot showing the data, imputed values and the linear regression model.
`y_lab`	Character vector of length one specifying the name of the dependent variable to appear as the y-axis label on plot showing the data, imputed values and the linear regression model.

List comprising a

Data data frame containing the original data plus an additional column named Value where the NA values of the Variable of interest have been imputed where possible.
Model linear regression model parameters including its coefficient of determination

and a scatter plot of the data (black points), linear regression model (red line) and fitted (imputed) values (blue points).

####Objective: Fill in missing values at groundwater well G_3356 using record at G_3355
##Viewing first few rows of G_3356
head(G_3356)
#Converting date column to a "Date" object
G_3356$Date<-seq(as.Date("1985-10-23"), as.Date("2019-05-29"), by="day")
#Converting readings to numeric object
G_3356$Value<-as.numeric(as.character(G_3356$Value))

##Viewing first few rows of G_3355
head(G_3355)
#Converting date column to a "Date" object
G_3355$Date<-seq(as.Date("1985-08-20"), as.Date("2019-06-02"), by="day")
#Converting readings to numeric object
G_3355$Value<-as.numeric(as.character(G_3355$Value))

##Merge the two dataframes by date
library('dplyr')
GW_S20<-merge(G_3356,G_3355,by="Date")
colnames(GW_S20)<-c("Date","G3356","G3355")
#Carrying out imputation
Imputation(Data=GW_S20,Variable="G3356",
           x_lab="Groundwater level (ft NGVD 29)",
           y_lab="Groundwater level (ft NGVD 29)")