Let $Y_n = fracsum_i=1^n X_i(X_i+1)n$ . Find a number $c$ such that $Y_n to c$

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Let $X_1, X_2, . . . , X_n$ be independent and identically distributed random variables, each
having a $Uniform[0, 0.5]$ distribution. Let $Y_n = fracsum_i=1^n X_i(X_i+1)n$
. Find a number $c$ such that
$Y_n to c$ ($p$ above the arrow)



Attempt:



$Y_n = fracsum_i=0^n X_i(X_i+1)n = fracsum_i=1^n X_i^2n + fracsum_i=1^n X_in$



Not sure how to go about this. I believe I need to find their expectation but not sure how.







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    Let $X_1, X_2, . . . , X_n$ be independent and identically distributed random variables, each
    having a $Uniform[0, 0.5]$ distribution. Let $Y_n = fracsum_i=1^n X_i(X_i+1)n$
    . Find a number $c$ such that
    $Y_n to c$ ($p$ above the arrow)



    Attempt:



    $Y_n = fracsum_i=0^n X_i(X_i+1)n = fracsum_i=1^n X_i^2n + fracsum_i=1^n X_in$



    Not sure how to go about this. I believe I need to find their expectation but not sure how.







    share|cite|improve this question






















      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      Let $X_1, X_2, . . . , X_n$ be independent and identically distributed random variables, each
      having a $Uniform[0, 0.5]$ distribution. Let $Y_n = fracsum_i=1^n X_i(X_i+1)n$
      . Find a number $c$ such that
      $Y_n to c$ ($p$ above the arrow)



      Attempt:



      $Y_n = fracsum_i=0^n X_i(X_i+1)n = fracsum_i=1^n X_i^2n + fracsum_i=1^n X_in$



      Not sure how to go about this. I believe I need to find their expectation but not sure how.







      share|cite|improve this question












      Let $X_1, X_2, . . . , X_n$ be independent and identically distributed random variables, each
      having a $Uniform[0, 0.5]$ distribution. Let $Y_n = fracsum_i=1^n X_i(X_i+1)n$
      . Find a number $c$ such that
      $Y_n to c$ ($p$ above the arrow)



      Attempt:



      $Y_n = fracsum_i=0^n X_i(X_i+1)n = fracsum_i=1^n X_i^2n + fracsum_i=1^n X_in$



      Not sure how to go about this. I believe I need to find their expectation but not sure how.









      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Aug 11 at 0:35









      Bas bas

      39611




      39611




















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          The density is $2$ on $(0,0.5)$ and $0$ elsewhere. $EX_1=2 int _0^ 1/2 x , dx =frac 1 4$ and $EX_1^2=2int _0^ 1/2 x ^2, dx =frac 1 12$ so $c=frac 1 4+frac 1 12= frac 1 3$.






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            By the Law of Large Numbers $$fracsum_i=0^n X_in rightarrow mu$$
            where $$mu = E(X) = frac12(0 + 0.5) = frac14$$
            Also
            $$fracsum_i=0^n X_i^2n rightarrow mu^2 + Var(X)$$
            where $$Var(X) = frac112(0.5)^2 = frac148 $$
            So
            $$fracsum_i=0^n X_i^2n rightarrow frac116 + frac148$$
            Therefore
            $$c = frac14 + frac116 + frac148 = frac13$$






            share|cite|improve this answer




















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              2 Answers
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              2 Answers
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              The density is $2$ on $(0,0.5)$ and $0$ elsewhere. $EX_1=2 int _0^ 1/2 x , dx =frac 1 4$ and $EX_1^2=2int _0^ 1/2 x ^2, dx =frac 1 12$ so $c=frac 1 4+frac 1 12= frac 1 3$.






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                up vote
                0
                down vote



                accepted










                The density is $2$ on $(0,0.5)$ and $0$ elsewhere. $EX_1=2 int _0^ 1/2 x , dx =frac 1 4$ and $EX_1^2=2int _0^ 1/2 x ^2, dx =frac 1 12$ so $c=frac 1 4+frac 1 12= frac 1 3$.






                share|cite|improve this answer






















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                  up vote
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                  The density is $2$ on $(0,0.5)$ and $0$ elsewhere. $EX_1=2 int _0^ 1/2 x , dx =frac 1 4$ and $EX_1^2=2int _0^ 1/2 x ^2, dx =frac 1 12$ so $c=frac 1 4+frac 1 12= frac 1 3$.






                  share|cite|improve this answer












                  The density is $2$ on $(0,0.5)$ and $0$ elsewhere. $EX_1=2 int _0^ 1/2 x , dx =frac 1 4$ and $EX_1^2=2int _0^ 1/2 x ^2, dx =frac 1 12$ so $c=frac 1 4+frac 1 12= frac 1 3$.







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                  answered Aug 11 at 0:41









                  Kavi Rama Murthy

                  21.8k2932




                  21.8k2932




















                      up vote
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                      down vote













                      By the Law of Large Numbers $$fracsum_i=0^n X_in rightarrow mu$$
                      where $$mu = E(X) = frac12(0 + 0.5) = frac14$$
                      Also
                      $$fracsum_i=0^n X_i^2n rightarrow mu^2 + Var(X)$$
                      where $$Var(X) = frac112(0.5)^2 = frac148 $$
                      So
                      $$fracsum_i=0^n X_i^2n rightarrow frac116 + frac148$$
                      Therefore
                      $$c = frac14 + frac116 + frac148 = frac13$$






                      share|cite|improve this answer
























                        up vote
                        1
                        down vote













                        By the Law of Large Numbers $$fracsum_i=0^n X_in rightarrow mu$$
                        where $$mu = E(X) = frac12(0 + 0.5) = frac14$$
                        Also
                        $$fracsum_i=0^n X_i^2n rightarrow mu^2 + Var(X)$$
                        where $$Var(X) = frac112(0.5)^2 = frac148 $$
                        So
                        $$fracsum_i=0^n X_i^2n rightarrow frac116 + frac148$$
                        Therefore
                        $$c = frac14 + frac116 + frac148 = frac13$$






                        share|cite|improve this answer






















                          up vote
                          1
                          down vote










                          up vote
                          1
                          down vote









                          By the Law of Large Numbers $$fracsum_i=0^n X_in rightarrow mu$$
                          where $$mu = E(X) = frac12(0 + 0.5) = frac14$$
                          Also
                          $$fracsum_i=0^n X_i^2n rightarrow mu^2 + Var(X)$$
                          where $$Var(X) = frac112(0.5)^2 = frac148 $$
                          So
                          $$fracsum_i=0^n X_i^2n rightarrow frac116 + frac148$$
                          Therefore
                          $$c = frac14 + frac116 + frac148 = frac13$$






                          share|cite|improve this answer












                          By the Law of Large Numbers $$fracsum_i=0^n X_in rightarrow mu$$
                          where $$mu = E(X) = frac12(0 + 0.5) = frac14$$
                          Also
                          $$fracsum_i=0^n X_i^2n rightarrow mu^2 + Var(X)$$
                          where $$Var(X) = frac112(0.5)^2 = frac148 $$
                          So
                          $$fracsum_i=0^n X_i^2n rightarrow frac116 + frac148$$
                          Therefore
                          $$c = frac14 + frac116 + frac148 = frac13$$







                          share|cite|improve this answer












                          share|cite|improve this answer



                          share|cite|improve this answer










                          answered Aug 11 at 0:45









                          Ahmad Bazzi

                          3,0601419




                          3,0601419






















                               

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