What is the probability that a class of 30 students out of 300 would have a final average grade higher than a 90?
95 96 94 58
67 94 89 88
97 76
50 94 61 63
78 90 79 81
98 64
86 91 92 95
85 79 89 88
95 92
94 65 40 80
93 81 95 89
91 88
96 58 88 77
98 91 97 79
93 94
92 91 61 74
90 89 80 95
96 91
80 95 90 85
77 58 98 99
100 97
95 89 85 86
71 78 88 94
72 68
97 83 88 62
89 93 42 98
89 59
88 79 95 93
80 92 96 93
89 86
96 99 93 77
59 93 89 88
92 93
88 97 80 89
93 86 95 97
93 35
68 99 94 84
58 67 93 98
88 98
88 85 84 92
80 87 95 90
93 98
93 91 89 64
96 87 91 95
96 84
89 88 97 65
97 88 79 95
92 58
75 83 95 91
92 87 89 84
89 92
60 86 87 46
91 93 95 96
98 83
93 98 83 75
97 59 93 89
47 94
86 91 92 95
88 83 87 95
88 96
93 79 85 95
78 80 81 89
97 89
89 95 94 88
68 85 83 95
84 78
89 87 98 80
93 96 88 97
82 93
43 87 54 93
95 97 93 87
94 94
92 90 95 68
83 88 93 95
89 97
93 79 87 95
97 89 96 91
98 86
86 89 56 68
91 98 64 97
96 95
89 88 85 79
95 96 94 57
99 79
95 97 96 77
75 60 87 67
63 84
95 96 91 89
93 95 69 86
61 53
In: Statistics and Probability
Which of the following investments is riskier? Why?
| Probability | Rate of | Rate of | Rate of |
| of Occurrence | Return | Return | Return |
| A | B | C | |
| 0.20 | 2.00% | 4.00% | 2.00% |
| 0.25 | 4.00% | 4.00% | 2.30% |
| 0.40 | 5.50% | 4.50% | 6.00% |
| 0.15 | 6.00% | 6.00% | 7.50% |
In: Finance
For certain software, independently of other users, the probability is 0.07 that a user encounters a fault. What are the chances of the 30th user is the 5th person encountering a fault?
In: Statistics and Probability
A queue with one server without buffer, the probability of a customer’ arrival and departure in a time unit is p and q respectively. Please try to 1) give the one step state transition probability matrix. 2) give the balance equations. 3) calculate the limiting probabilities for p=0.3 and q=0.5. (12 points)
In: Statistics and Probability
Two teams, A and B, are playing a series of games. Assume
1. probability that A won a game is p
2. result of a game will not aect result of the next game
Find the range of p such that team A has the advantage in a best four of seven series.
In: Statistics and Probability
Compute the relative probability of finding an electron at the bottom of the conduction band relative to the probability of finding an electron at the top of the valence band in a silicon crystal at a temperature of (a) 3 K and (b) 300 K. Use Fermi-Dirac statistics. Compare your answer with the one given by the Boltzmann equation.
In: Physics
Given a normal distribution with u = 70 and o= 20, what is the probability that
In: Statistics and Probability
1a.) If two events A and B are non-overlapping, then the formula for computing the probability of theirunion is: ?(?) + ?(?) . This statement is true or false?
1b.) A survey of 1,000 adults in a small town gave the following data. Round answers to the nearest tenth of a percent.
If an adult in the town is selected at random, find the probability that: a.) The adult is either female or employed.
b.) The adult is neither male nor employed.
c.) The adult is female, given the adult is unemployed.
d.) The adult is unemployed, given the adult is female.
|
Employed |
Unemployed |
Total |
|
|
Male |
510 |
40 |
550 |
|
Female |
190 |
260 |
450 |
|
Total |
700 |
300 |
1,000 |
In: Statistics and Probability
Assuming that P equals .60 and the sample size is 1,000, what is the probability of observing a sample proportion that is at least .64.
In: Statistics and Probability
Theory: A vector with nonnegative entries is called a probability vector if the sum of its entries is 1. A square matrix is called right stochastic matrix if its rows are probability vectors; a square matrix is called a left stochastic matrix if its columns are probability vectors; and a square matrix is called a doubly stochastic matrix if both the rows and the columns are probability vectors.
**Write a MATLAB function
function [S1,S2,P]=stochastic(A)
which accepts a square matrix A with nonnegative entries as an input. An output P will be a stochastic matrix, when it can be created according to the instructions given below. You will also calculate and output the row vectors S1=sum(A,1) and S2=transpose(sum(A,2)) in your code, where the entries of the vectors sum(A,1) and sum(A,2) are the sums of the entries of A down each column and across each row, respectively You may also employ the conditional “if” statements and logical function all.
**First, the function has to check whether a matrix A contains both a zero column and a zero row. If yes, the output has to be a message “A is not stochastic and cannot be scaled to stochastic”. (Meaning: it is neither right- nor left-stochastic and cannot be scaled to either of them.) The output P in this case will be an empty matrix, P= [ ].
**Then, the function checks whether a matrix A is: (1) doubly stochastic, (2) only left stochastic, (3) only right stochastic, or (4) neither left nor right stochastic but can be scaled to stochastic.
In the cases (1)-(3), output the corresponding messages that comment on the types of the matrices and assign to the output P the matrix A itself.
**When you are working with the case (4), output a message “neither left nor right stochastic but can be scaled to stochastic”. If the vector S1 does not have any zero entry, use this vector to modify A into a left-stochastic matrix P by scaling each of its columns by the reciprocal of the corresponding entry of S1, and output a message that you are scaling A to a left-stochastic matrix P. If S1 has a zero entry, use the vector S2 to modify matrix A into a right-stochastic matrix P by scaling each of its rows by the reciprocal of the corresponding entry of S2, and output a message that you are scaling A to a right-stochastic matrix P. Output the matrix P.
**Type the function stochastic in your Live Script.
**Run the function [S1,S2,P]=stochastic(A) on each of the matrices below (display the matrices in your Live Script file):
(a)A=[0.5, 0, 0.5; 0, 0, 1; 0.5, 0, 0.5]
(b)A = transpose(A)
(c)A=[0.5, 0, 0.5; 0, 0, 1; 0, 0, 0.5]
(d)A=transpose(A)
(e)A=[0.5, 0, 0.5; 0, 0.5, 0.5; 0.5, 0.5, 0]
(f)A=magic(3)
(g)A=diag([1,2,3])
(h)A=[0, 0, 0; 0, 0.5, 0.5; 0, 0.5, 0.5]
(k)A=randi(10,5,5);A(:,1)=0;A(1,:)=0
NOTE: Make sure that you will verify that your outputs and the messages match the corresponding definitions of stochastic matrices. If they don’t, make corrections in your code!
In: Advanced Math