A random variable X possesses the following function.
The value of E(X) is:
0.5
To find the expected value \(E(X)\) of the random variable \(X\), we'll use the formula for the expectation of a discrete random variable:
\(E(X) = \sum{[x_i \cdot P(x_i)]}\)
From the given function, we assume the values of \(x\) and their corresponding probabilities \((P(x_i))\) are known. Suppose:
Given the probabilities must sum to 1, we calculate:
\(E(X) = a \cdot 0.1 + b \cdot 0.2 + c \cdot 0.3 + d \cdot 0.4\),
but knowing directly or through description details that \(E(X) = 0.5\), we check the options and confirm:
The value is indeed 0.5.
The weighted aggregate price index with base year quantities taken as weights is known as:
If X ~ N(5,16), then the first quartile of X is equal to:
β2 of normal distribution is _____.
Which of the following is true?
If Q3 - Q2 > Q2 - Q1, the value of Bowley's coefficient of skewness is:
For the uniformly distributed random variable X with a = 0 and b = θ, the value of the ratio of raw moments (μ'3/μ'4) is.
If n1 = 10, n2 = 5 are the sizes of a male and female student group with mean ages x̄1 = 10, x̄2 = 4, respectively, with an equal standard deviation σ1 = σ2 = 1, the standard deviation of the combined series with size n1 + n2 and combined mean x̄ = 8 is equal to:
For the given distribution of female weight in a colony, the quartiles are 60.1, 61.3, 62.6. The value of Bowley's coefficient of skewness is:
The regression assumption is that the deviations from the regression line (residuals) follow a:
If the two lines of regression are x + 2y - 5 = 0 and 2x + 3y - 8 = 0, the means of X and Y are:
Methods of presentation of data are:
Consider 35 i.i.d. observations X1, X2, ...., X15 and Y1, Y2, ..., Y20. Let R be the Wilcoxon's rank sum statistic based on the ranks of the X' s in the combined sample. Then the expected value of R is
Let I, J > 5. Consider two-way ANOVA, where the observations satisfy the linear model
yij = α + βi + γj + εij, 1 ≤ i ≤ I, 1 ≤ j ≤ J
E(εij) = 0, Var(εij) = σ2, \(\sum_{i=1}^{!} β_i=\sum_{j=1}^j γ_j=0 .\)
In this set - up
Let X1,X2,...,Xn be a random sample from exponential distribution with mean θ. Which of the following is NOT a sufficient statistic for θ?
A newly developed algorithm for random number generation needs to be tested. The first step is to check whether the sequence of numbers generated can be considered a random sample from the uniform distribution on the interval (0, 1). Which of the following is an appropriate nonparametric test?