title: After setting seed, for how long or how many chunks of code will that seed be effective for?
body: <p>Really curious about this because previously when I ran a long chunk of codes involving 1000 simulations for a particular seed, second run gave different results. I was not sure where did the seed started to lose its effect and had to set seed again every time there is random number generation.</p>
  
  <p>So how does R know when to use the seed I gave it and when to use a random seed again?</p>