For a distribution, the mean is 10, variance is 16, γ 1is + 1 and β 2is 4. The distribution is:
leptokurtic
The shape of a distribution's tails is described by kurtosis, measured by \(\beta_2\). The benchmark is the normal distribution, for which \(\beta_2 = 3\) (mesokurtic).
Classification rule:
\[\beta_2 > 3 \Rightarrow \text{leptokurtic},\quad \beta_2 = 3 \Rightarrow \text{mesokurtic},\quad \beta_2 < 3 \Rightarrow \text{platykurtic}\]
Here \(\beta_2 = 4 > 3\), so the distribution is more peaked with heavier tails than normal. The skewness value \(\gamma_1 = +1\) only indicates positive asymmetry and does not affect the kurtosis label. Hence the distribution is leptokurtic.
If the data are skewed, which option of central tendency measure is the most unreliable indicator?
The Excess Kurtosis of the Geometric distribution with parameter p is:
For the discrete distribution, the Pearson's coefficient of skewness β 2is always:
60% of the employees of a company are college graduates. Of these, 10% are in sales. Of the employees who did not graduate from college, 80% are in sales. The probability that an employee selected at random is in sales, is:
The probability that a contractor gets a plumbing contract is 2 / 3 and the probability that he will not get an electric contract is 5 / 9. If the probability of getting at least one contract is 4 / 5, then the probability that he will get both the contracts is:
For a frequency distribution of a variable x, mean = 32, median = 30. The distribution is:
The first four raw moments of distribution are 2, 136, 320, and 40,000, The coefficient of skewness is:
For a distribution, the percentile partition values are P 10 = 58.983, P 50 = 61.345 and P 90 = 63.831. Kelly's coefficient of skewness is:
A box contains four soccer balls printed with numbers 112, 121, 211. 222. A footballer chooses one ball at random. Let A 1be the event that the first digit of the printed number of the ball chosen is 1. Similarly, A 2and A 3denote that second as well as third digit of the printed number is 1. The events A 1,A 2, and A 3are:
If the Bowley’s coefficient of skewness is less than zero, then the distribution is:
If the data are skewed, which option of central tendency measure is the most unreliable indicator?
Events A, Band C are mutually exclusive events such that \(P(A) = \dfrac{3x + 1}{3}, P(B) = \dfrac{1-x}{4}\)and \(P(C) = \dfrac{1-2x}{4}\)The set of possible values of x are in the interval
Let A, B be two events in a discrete probability space with ℙ(A) > 0 and ℙ(B) > 0. Which of the following are necessarily true?
The Excess Kurtosis of the Geometric distribution with parameter p is:
For the discrete distribution, the Pearson's coefficient of skewness β 2is always: