Expectation and RIP question











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Hi I am trying to solve the following question but couldnt figure out if i am moving in the right direction or not. The question is as follows.



I have a large number of candies. One day i decided to distribute them to my friends. Suppose 10 of my friends have a collection of
1000 candies each, the other 15 have a collection of 1300 candies each while the rest of your 5 friends have collected 600
candies each.




  1. What is the average number of candies your friends have?


  2. If you mix all of these candies and randomly pick one out, what is the expected size of the collection that candies's
    owner has?



I am trying to approach this problem Through Random Incidence Paradox. Am i doing correct can any one help me out here.










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    Don´t forget to accept one of the given answers. Check your previous questions. Hint: At 1. you just have to calculate the arithmetic mean.
    – callculus
    Nov 17 at 18:50

















up vote
0
down vote

favorite












Hi I am trying to solve the following question but couldnt figure out if i am moving in the right direction or not. The question is as follows.



I have a large number of candies. One day i decided to distribute them to my friends. Suppose 10 of my friends have a collection of
1000 candies each, the other 15 have a collection of 1300 candies each while the rest of your 5 friends have collected 600
candies each.




  1. What is the average number of candies your friends have?


  2. If you mix all of these candies and randomly pick one out, what is the expected size of the collection that candies's
    owner has?



I am trying to approach this problem Through Random Incidence Paradox. Am i doing correct can any one help me out here.










share|cite|improve this question


















  • 1




    Don´t forget to accept one of the given answers. Check your previous questions. Hint: At 1. you just have to calculate the arithmetic mean.
    – callculus
    Nov 17 at 18:50















up vote
0
down vote

favorite









up vote
0
down vote

favorite











Hi I am trying to solve the following question but couldnt figure out if i am moving in the right direction or not. The question is as follows.



I have a large number of candies. One day i decided to distribute them to my friends. Suppose 10 of my friends have a collection of
1000 candies each, the other 15 have a collection of 1300 candies each while the rest of your 5 friends have collected 600
candies each.




  1. What is the average number of candies your friends have?


  2. If you mix all of these candies and randomly pick one out, what is the expected size of the collection that candies's
    owner has?



I am trying to approach this problem Through Random Incidence Paradox. Am i doing correct can any one help me out here.










share|cite|improve this question













Hi I am trying to solve the following question but couldnt figure out if i am moving in the right direction or not. The question is as follows.



I have a large number of candies. One day i decided to distribute them to my friends. Suppose 10 of my friends have a collection of
1000 candies each, the other 15 have a collection of 1300 candies each while the rest of your 5 friends have collected 600
candies each.




  1. What is the average number of candies your friends have?


  2. If you mix all of these candies and randomly pick one out, what is the expected size of the collection that candies's
    owner has?



I am trying to approach this problem Through Random Incidence Paradox. Am i doing correct can any one help me out here.







probability probability-theory probability-distributions expected-value






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asked Nov 17 at 18:48









chuffles

203




203








  • 1




    Don´t forget to accept one of the given answers. Check your previous questions. Hint: At 1. you just have to calculate the arithmetic mean.
    – callculus
    Nov 17 at 18:50
















  • 1




    Don´t forget to accept one of the given answers. Check your previous questions. Hint: At 1. you just have to calculate the arithmetic mean.
    – callculus
    Nov 17 at 18:50










1




1




Don´t forget to accept one of the given answers. Check your previous questions. Hint: At 1. you just have to calculate the arithmetic mean.
– callculus
Nov 17 at 18:50






Don´t forget to accept one of the given answers. Check your previous questions. Hint: At 1. you just have to calculate the arithmetic mean.
– callculus
Nov 17 at 18:50












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  1. Simply the weighted average: $frac{10 times 1000 + 15*1300 + 5*600}{10+15+5} = 1083.33$


  2. Group 1 brings $10 times 1000 = 10000$ candies to the mix, group 2 brings $15 times 1300 = 19500$ candies to the mix, and group 3 brings $5 times 600 = 3000$ candies to the mix. There are a total of 32500 candies. You will pick a candy from an friend from group 1 with probability $10000/32500 = 0.3076$, group 2 with probability 0.6, and group 3 with probability 0.0923. Thus, the owner will have a candy collection of 1000 w.p. 0.3076, 1300 w.p. 0.6 and 600 w.p. 0.0923. You can now compute the expected value as $0.3076 times 1000 + 0.6 times 1300 + .0923 times 600 = 1143.08$, which is not the same as part 1.



The random incidence paradox is a good framework to understand the details of this problem.






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    1. Simply the weighted average: $frac{10 times 1000 + 15*1300 + 5*600}{10+15+5} = 1083.33$


    2. Group 1 brings $10 times 1000 = 10000$ candies to the mix, group 2 brings $15 times 1300 = 19500$ candies to the mix, and group 3 brings $5 times 600 = 3000$ candies to the mix. There are a total of 32500 candies. You will pick a candy from an friend from group 1 with probability $10000/32500 = 0.3076$, group 2 with probability 0.6, and group 3 with probability 0.0923. Thus, the owner will have a candy collection of 1000 w.p. 0.3076, 1300 w.p. 0.6 and 600 w.p. 0.0923. You can now compute the expected value as $0.3076 times 1000 + 0.6 times 1300 + .0923 times 600 = 1143.08$, which is not the same as part 1.



    The random incidence paradox is a good framework to understand the details of this problem.






    share|cite|improve this answer

























      up vote
      1
      down vote














      1. Simply the weighted average: $frac{10 times 1000 + 15*1300 + 5*600}{10+15+5} = 1083.33$


      2. Group 1 brings $10 times 1000 = 10000$ candies to the mix, group 2 brings $15 times 1300 = 19500$ candies to the mix, and group 3 brings $5 times 600 = 3000$ candies to the mix. There are a total of 32500 candies. You will pick a candy from an friend from group 1 with probability $10000/32500 = 0.3076$, group 2 with probability 0.6, and group 3 with probability 0.0923. Thus, the owner will have a candy collection of 1000 w.p. 0.3076, 1300 w.p. 0.6 and 600 w.p. 0.0923. You can now compute the expected value as $0.3076 times 1000 + 0.6 times 1300 + .0923 times 600 = 1143.08$, which is not the same as part 1.



      The random incidence paradox is a good framework to understand the details of this problem.






      share|cite|improve this answer























        up vote
        1
        down vote










        up vote
        1
        down vote










        1. Simply the weighted average: $frac{10 times 1000 + 15*1300 + 5*600}{10+15+5} = 1083.33$


        2. Group 1 brings $10 times 1000 = 10000$ candies to the mix, group 2 brings $15 times 1300 = 19500$ candies to the mix, and group 3 brings $5 times 600 = 3000$ candies to the mix. There are a total of 32500 candies. You will pick a candy from an friend from group 1 with probability $10000/32500 = 0.3076$, group 2 with probability 0.6, and group 3 with probability 0.0923. Thus, the owner will have a candy collection of 1000 w.p. 0.3076, 1300 w.p. 0.6 and 600 w.p. 0.0923. You can now compute the expected value as $0.3076 times 1000 + 0.6 times 1300 + .0923 times 600 = 1143.08$, which is not the same as part 1.



        The random incidence paradox is a good framework to understand the details of this problem.






        share|cite|improve this answer













        1. Simply the weighted average: $frac{10 times 1000 + 15*1300 + 5*600}{10+15+5} = 1083.33$


        2. Group 1 brings $10 times 1000 = 10000$ candies to the mix, group 2 brings $15 times 1300 = 19500$ candies to the mix, and group 3 brings $5 times 600 = 3000$ candies to the mix. There are a total of 32500 candies. You will pick a candy from an friend from group 1 with probability $10000/32500 = 0.3076$, group 2 with probability 0.6, and group 3 with probability 0.0923. Thus, the owner will have a candy collection of 1000 w.p. 0.3076, 1300 w.p. 0.6 and 600 w.p. 0.0923. You can now compute the expected value as $0.3076 times 1000 + 0.6 times 1300 + .0923 times 600 = 1143.08$, which is not the same as part 1.



        The random incidence paradox is a good framework to understand the details of this problem.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Nov 18 at 3:41









        Aditya Dua

        5958




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