{"id":83,"date":"2016-11-10T22:02:30","date_gmt":"2016-11-10T22:02:30","guid":{"rendered":"http:\/\/codeclub.garethgwyther.co.uk\/?p=83"},"modified":"2016-11-10T22:02:30","modified_gmt":"2016-11-10T22:02:30","slug":"microbit-monty-hall-problem","status":"publish","type":"post","link":"https:\/\/codeclub.garethgwyther.co.uk\/?p=83","title":{"rendered":"MicroBit Monty Hall problem"},"content":{"rendered":"

Today we are going to construct a small game using the micro-bit which using an idea below.<\/p>\n

https:\/\/en.wikipedia.org\/wiki\/Monty_Hall_problem<\/p>\n

Suppose you’re on a game show, and you’re given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No.\u00a01, and the host, who knows what’s behind the doors, opens another door, say No.\u00a03, which has a goat. He then says to you, “Do you want to pick door No.\u00a02?” Is it to your advantage to switch your choice?<\/p>\n

Vos Savant’s response was that the contestant should switch to the other door (vos Savant 1990a<\/a>). Under the standard assumptions, contestants who switch have a 2\/<\/span>3<\/span> chance of winning the car, while contestants who stick to their initial choice have only a 1\/<\/span>3<\/span> chance.<\/p>\n

So we are going to create a game based on the above theory to prove it right or wrong.<\/p>\n

List<\/strong> Prizes
\nStrings<\/strong>
\nGoat
\nCar
\nGoat<\/p>\n

    \n
  1. Go to this page\u00a0Click here to start<\/a><\/li>\n
  2. Create a list in python and print position 0 in the list.\n
    \nprizes = [\"Goat\",\"Goat\",\"Car\"]\nprint(prizes[0])\n<\/pre>\n<\/li>\n
  3. This return the same thing over and over again.<\/li>\n
  4. We need to randomise the list.<\/li>\n
  5. Place this code above prizes\n
    from random import shuffle\nfrom random import randint<\/pre>\n<\/li>\n
  6. Then before the print and after prizes and in this line\n
    shuffle(prizes)<\/pre>\n<\/li>\n
  7. Run the code this should now be randomised you should not see car appearing every so often<\/li>\n
  8. Code should now look like this.\n
    \nfrom random import shuffle\nfrom random import randint\nprizes = [\"Goat\",\"Goat\",\"Car\"]\nshuffle(prizes)\nprint(prizes[0])\n<\/pre>\n<\/li>\n
  9. We now need to ask a question remove the rint(prizes[0])and replace with below.\n
    \nprint(\"Monty: Please select a door between 0 and 2\")\ndoor = input()\nprint(\"Monty: You Selected door number \"+door)\n<\/pre>\n<\/li>\n
  10. Code should now look like this.\n
    \nfrom random import shuffle\nfrom random import randint\nprizes = [\"Goat\",\"Goat\",\"Car\"]\nshuffle(prizes)\nprint(\"Monty: Please select a door between 0 and 2\")\ndoor = input()\nprint(\"Monty: You Selected door number \"+door)\n<\/pre>\n<\/li>\n
  11. Due to input() being not forced as int we need to convert it an integer add this after
    \nfrom random import randint<\/p>\n
    \ndef convertStr(s):\n    try:\n        ret = int(s)\n    except ValueError:\n        ret = float(s)\n    return ret\n\n<\/pre>\n<\/li>\n
  12. \nYou’re code should now look like this.<\/p>\n
    \nfrom random import shuffle\nfrom random import randint\n\ndef convertStr(s):\n    try:\n        ret = int(s)\n    except ValueError:\n        ret = float(s)\n    return ret\n\nprizes = [\"Goat\",\"Goat\",\"Car\"]\nshuffle(prizes)\nprint(\"Monty: Please select a door between 0 and 2\")\ndoor = input()\nprint(\"Monty: You Selected door number \"+door)\n<\/pre>\n<\/li>\n
  13. \ndef declares what is known as a function
    \nfunctions can take parameters (variables input etc)
    \nin this case we want the input of door
    \nAdd this code after the print(“You Selected door number “+door)<\/p>\n
    \nselected_door_int = convertStr(door)\n<\/pre>\n<\/li>\n
  14. \nOur presenter Monty needs to select a door add this code after selected_door_int = convertStr(door)<\/p>\n
    \nprint(\"MONTY: I will now select a door\")\npresenter_door = randint(0,2)\nwhile 1:\n    if presenter_door != selected_door_int or prizes[presenter_door] != \"Car\":\n    \tpresenter_door = randint(0,2)\n    break\nprint(\"MONTY: I selected door number \"+str(presenter_door)+\" and my prize was a \"+prizes[presenter_door]);\n<\/pre>\n<\/li>\n
  15. \nYou’re code should now look like this.<\/p>\n
    \nfrom random import shuffle\nfrom random import randint\n\ndef convertStr(s):\n    try:\n        ret = int(s)\n    except ValueError:\n        ret = float(s)\n    return ret\n\nprizes = [\"Goat\",\"Goat\",\"Car\"]\nshuffle(prizes)\nprint(\"MONTY: Please select a door between 0 and 2\")\ndoor = input()\nprint(\"You Selected door number \"+door)\nselected_door_int = convertStr(door)\nprint(\"MONTY:I will now select a door\")\npresenter_door = randint(0,2)\nwhile 1:\n    if presenter_door == selected_door_int or prizes[presenter_door] == \"Car\":\n    \tpresenter_door = randint(0,2)\n    break\nprint(\"I selected door number \"+str(presenter_door)+\" and my prize was a \"+prizes[presenter_door]);\n<\/pre>\n<\/li>\n
  16. presenter_door = randint(0,2) this means select a random number between 0 and 1 (0,1,2) this is all the indexs of our list<\/li>\n
  17.  While 1: means star the loop<\/li>\n
  18.  if presenter_door == selected_door_int or prizes[presenter_door] == “Car”: this means if either conidtion is met (presenter door equals door person has selected or prize of selected index equals car remember Monty is not allowed to select the car)<\/li>\n
  19. Now for the final element should the person take a risk or not according to the statistical nature of above they should<\/li>\n
  20. Add this code after print(“I selected door number “+str(presenter_door)+” and my prize was a “+prizes[presenter_door]);\n
    \nprint(\"MONTY: Do you want to change you're mind on you're door type Yes Or No?\")\nanswer = input()\nprint(\"MONTY: You selected \"+answer)\nif answer.lower() == \"no\":\n    print(\"You have won a \"+prizes[selected_door_int])\nelse:\n\tfinal_door = randint(0,2)\n        while 1:\n            if final_door == selected_door_int or presenter_door == final_door:\n                final_door = randint(0,2)\n            break\n\tprint(\"You have won a \"+prizes[final_door])\n<\/pre>\n<\/li>\n
  21. Code should now look like this.\n
    \nfrom random import shuffle\nfrom random import randint\n\ndef convertStr(s):\n    try:\n        ret = int(s)\n    except ValueError:\n        ret = float(s)\n    return ret\n\nprizes = [\"Goat\",\"Goat\",\"Car\"]\nshuffle(prizes)\nprint(\"MONTY: Please select a door between 0 and 2\")\ndoor = input()\nprint(\"You Selected door number \"+door)\nselected_door_int = convertStr(door)\nprint(\"MONTY:I will now select a door\")\npresenter_door = randint(0,2)\nwhile 1:\n    if presenter_door == selected_door_int or prizes[presenter_door] == \"Car\":\n    \tpresenter_door = randint(0,2)\n    break\nprint(\"MONTY: I selected door number \"+str(presenter_door)+\" and my prize was a \"+prizes[presenter_door]);\nprint(\"MONTY: Do you want to change you're mind on you're door type Yes Or No?\")\nanswer = input()\nprint(\"MONTY: You selected \"+answer)\nif answer.lower() == \"no\":\n    print(\"You have won a \"+prizes[selected_door_int])\nelse:\n\tfinal_door = randint(0,2)\n        while 1:\n            if final_door == selected_door_int or presenter_door == final_door:\n                final_door = randint(0,2)\n            break\n\tprint(\"You have won a \"+prizes[final_door])\n<\/pre>\n<\/li>\n
  22. We now need to convert this to microbit code go here <\/a><\/li>\n
  23. We are presented with the code as follows\n
    \n# Add your Python code here. E.g.\nfrom microbit import *\n\n\nwhile True:\n    display.scroll('Hello, World!')\n    display.show(Image.HEART)\n    sleep(2000)\n\n<\/pre>\n<\/li>\n
  24. \nLets starting adding our code<\/p>\n
    \n# Add your Python code here. E.g.\nfrom microbit import *\nimport random\n\n\nprizes = [\"Goat\",\"Goat\",\"Car\"]\ndoor = 0\nwhile True:\n    display.scroll('MONTY: Please select a door')\n    display.clear()\n    if button_a.get_presses() or button_b.get_presses():\n        door = random.randint(0,2)\n        display.clear()\n        text = \"Monty: You Selected door number \"+str(door)\n        display.scroll(text)\n        display.clear()\n        display.scroll(\"Monty: I will now select a door\")\n     \tpresenter_door = random.randint(0,2)\n        while 1:\n            if presenter_door == door or prizes[presenter_door] == \"Car\":\n                presenter_door = random.randint(0,2)\n            break\n        display.scroll(\"MONTY: I selected door number \"+str(presenter_door)+\" and my prize was a \"+prizes[presenter_door])\n        display.clear()\n        display.scroll(\"MONTY: Do you want to change you're mind on you're door type Yes(a) Or No(b)?\")\n     \tif button_a.get_presses():\n            final_door = random.randint(0,2)\n            while 1:\n                if final_door == door or presenter_door == final_door:\n                    final_door = random.randint(0,2)\n                break\n            display.scroll(\"You have won a \"+prizes[final_door])\n        elif button_b.get_presses(): \n            display.scroll(\"You have won a \"+prizes[door])\n<\/pre>\n<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"
    Today we are going to construct a small game using the micro-bit which using an idea below. https:\/\/en.wikipedia.org\/wiki\/Monty_Hall_problem Suppose you’re on a game show, and you’re given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No.\u00a01, and the host, who knows what’s behind […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-83","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/83","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=83"}],"version-history":[{"count":0,"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/83\/revisions"}],"wp:attachment":[{"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=83"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=83"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/codeclub.garethgwyther.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=83"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}