\documentclass{article}
\usepackage{tikz}
\usepackage{pgfplots}
\pgfplotsset{compat=1.13}

\begin{document}

	
	\begin{tikzpicture}[scale=1.5,
	X/.style = {circle, fill=black, inner sep=1.5pt, 
		label={[font=\scriptsize]above right:#1},
		node contents={}}
	]
	\begin{axis}[
	domain=0:2,
	xtick={0,1,2},
	ytick={1,2},
	axis lines=left,
	%grid=both,
	%clip=false,
	xlabel=\textit{$\lambda$},
	ylabel=\textit{$\mu$}
	]
	\addplot [smooth,thick,black]coordinates { (0,1) (1,1) };
	\addplot [smooth,thick,black]coordinates { (1,0) (1,1) };
	\addplot [dashed,thick,black]coordinates { (0,2) (2,2) };
	\addplot [dashed,thick,black]coordinates { (2,0) (2,2) };
	%
	\draw[dashed] (0,0) -- (0,0) node[X={\textbf{P}$(\lambda=0, \mu=0)$}] -- (0,0);
	\draw[dashed] (0,0) -- (0,1) node[X={\textbf{PD}$(\lambda=0, \mu=1)$}] -- (1,1);
	\draw[dashed] (0,0) -- (1,0) node[X={\textbf{PI}$(\lambda=1, \mu=0)$}] -- (1,1);
	\draw[dashed] (1,0) -- (1,1) node[X={\textbf{PID}$(\lambda=1, \mu=1)$}] -- (1,1);
	\end{axis}
	\end{tikzpicture}
\end{document}