如何找到最大似然估计器？

Question

我已经生成了1000个泊松分布样本，并试图绘制概率密度函数和最大似然估计图。我已经完成了概率密度函数图，但是我不知道如何找到数据集的MLE以及绘制MLE图的方法

#1000 samples with sample size n = 100#
set.seed(124)
library(ggplot2)
library(tidyr)


#generating 1000 samples with sample size n = 100 with Poission Distribution with parameter lambda = 3#
Sample1000 <- replicate(1000, matrix(data=rpois(100, lambda = 3),ncol = 1), simplify = TRUE)
Graph1000 <- gather(as.data.frame(Sample1000))
View(Sample1000)

colMeans(Sample1000)
apply(Sample1000, 2, var)

#plot the pdf graph for 1000 samples set#
ggplot(Graph1000, aes(x = value)) +
  geom_density(aes(group = key)) +
  labs(x = "y", y = "P(y)", title = "Probability density function for 1000 samples") +
  theme_classic() +
  theme(plot.title = element_text(hjust = 0.5)) + 
  scale_x_continuous(breaks = seq(from = 0,to = 14,by = 2), limits = c(0,14))  +
  scale_y_continuous(expand = c(0,0))

我期望图形像图像显示