Measures of Dispersion, Skewness and Kurtosis MCQs 2026
60 questions with detailed answers · 21 from past papers · 6 quiz batches available
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- Q1 hard
If mean = 30, mode = 24, SD = 3, Pearson skewness (mode) is
💡 Explanation:(30−24)/3 = 2 (positive skew).
- Q2 Past Paper · PPSC/FPSC/CSS easy
Dispersion measures
💡 Explanation:Spread complements central tendency.
- Q3 Past Paper · PPSC/FPSC/CSS easy
Range is defined as
💡 Explanation:Range = Xmax − Xmin.
- Q4 Past Paper · PPSC/FPSC/CSS easy
Range of 4, 7, 9, 15 is
💡 Explanation:15 − 4 = 11.
- Q5 Past Paper · PPSC/FPSC/CSS medium
Mean deviation (MD) is
💡 Explanation:MD = Σ|x − mean| / n.
- Q6 Past Paper · PPSC/FPSC/CSS hard
For 2, 4, 6 with mean 4, mean deviation from mean is
💡 Explanation:Deviations: 2,0,2; sum abs = 4; MD = 4/3.
- Q7 Past Paper · PPSC/FPSC/CSS easy
Variance measures
💡 Explanation:Variance emphasizes larger deviations.
- Q8 Past Paper · PPSC/FPSC/CSS easy
Population variance is Σ(x − μ)² /
💡 Explanation:Population divides by N.
- Q9 Past Paper · PPSC/FPSC/CSS medium
Sample variance s² uses divisor
💡 Explanation:n−1 gives unbiased estimate of population variance.
- Q10 Past Paper · PPSC/FPSC/CSS medium
For data 2, 4, 6 (sample), sample variance is
💡 Explanation:Deviations −2,0,2; squared sum = 8; s² = 8/(3−1) = 4.
- Q11 Past Paper · PPSC/FPSC/CSS medium
For data 2, 4, 6 (population), population variance is
💡 Explanation:8/3 ≈ 2.67.
- Q12 Past Paper · PPSC/FPSC/CSS easy
Standard deviation is
💡 Explanation:SD = √variance.
- Q13 Past Paper · PPSC/FPSC/CSS easy
If sample variance is 25, standard deviation is
💡 Explanation:√25 = 5.
- Q14 Past Paper · PPSC/FPSC/CSS medium
Coefficient of variation (CV) is
💡 Explanation:CV compares relative variability across scales.
- Q15 Past Paper · PPSC/FPSC/CSS easy
If mean = 50 and SD = 10, CV is
💡 Explanation:(10/50)×100 = 20%.
- Q16 easy
A dataset with SD = 0 must have
💡 Explanation:Zero spread means no deviation from a single value.
- Q17 hard
Pearson's coefficient of skewness using mode is (Mean − Mode) /
💡 Explanation:Skewness = (Mean − Mode)/SD.
- Q18 Past Paper · PPSC/FPSC/CSS medium
Quartile deviation is (Q3 − Q1) /
💡 Explanation:Semi-interquartile range = IQR/2.
- Q19 easy
Negative skewness means
💡 Explanation:Left-skew pulls mean downward.
- Q20 Past Paper · PPSC/FPSC/CSS easy
A larger standard deviation indicates
💡 Explanation:SD increases as observations differ more from mean.
- Q21 Past Paper · PPSC/FPSC/CSS easy
If all values in a dataset are identical, standard deviation is
💡 Explanation:No variation implies SD = 0.
- Q22 hard
Bowley's coefficient of skewness uses
💡 Explanation:Quartile skewness is robust to outliers.
- Q23 easy
For symmetric data, coefficient of skewness is
💡 Explanation:Symmetry implies balanced tails.
- Q24 medium
Kurtosis measures
💡 Explanation:Kurtosis describes shape of top and tails.
- Q25 medium
For a normal (mesokurtic) distribution, kurtosis (Pearson, moment-based) equals
💡 Explanation:Standard normal has kurtosis 3.
- Q26 hard
Excess kurtosis is defined as
💡 Explanation:Normal excess kurtosis = 0.
- Q27 hard
Leptokurtic distribution has
💡 Explanation:Leptokurtic: more outlier-prone.
- Q28 hard
Platykurtic distribution has
💡 Explanation:Platykurtic is flatter than mesokurtic.
- Q29 hard
Chebyshev's inequality states that for any k > 1, at least (1 − 1/k²) of data lie within
💡 Explanation:Applies to any distribution with finite variance.
- Q30 hard
By Chebyshev, at least what fraction lies within 2 SD of the mean
💡 Explanation:1 − 1/2² = 3/4 = 75%.
- Q31 hard
By Chebyshev, at least what fraction lies within 3 SD of the mean
💡 Explanation:1 − 1/9 = 8/9.
- Q32 medium
Mean deviation is generally considered
💡 Explanation:Squared deviations lead to useful algebraic properties.
- Q33 medium
Standard deviation is preferred in inference because
💡 Explanation:SD links to variance and many statistical models.
- Q34 easy
If two datasets have the same mean but different SD, the riskier investments typically have
💡 Explanation:Greater SD implies more variability.
- Q35 medium
Comparing variability of heights (cm) and weights (kg) fairly uses
💡 Explanation:CV is unit-free relative measure.
- Q36 medium
For grouped data, variance can be computed using
💡 Explanation:Grouped formulas use midpoints as xi.
- Q37 hard
Root mean square deviation equals
💡 Explanation:RMS of deviations is SD when based on squared mean.
- Q38 easy
A distribution with mean 100 and SD 5 has CV of
💡 Explanation:(5/100)×100 = 5%.
- Q39 hard
If variance increases by multiplying each value by 2, new variance is
💡 Explanation:Var(aX) = a² Var(X); 2² = 4.
- Q40 hard
Semi-average range is
💡 Explanation:Half-sample ranges averaged estimate spread.
- Q41 medium
Skewness zero and kurtosis 3 suggest
💡 Explanation:Matches normal-like shape reference.
- Q42 easy
In PPSC/CSS, dispersion questions often include
💡 Explanation:Exams test computation and interpretation of spread.
- Q43 medium
Population variance of 1, 4, 7 is
💡 Explanation:Mean = 4; squared deviations 9+0+9 = 18; σ² = 18/3 = 6.
- Q44 medium
Population standard deviation of 1, 4, 7 is
💡 Explanation:SD = √6 ≈ 2.45.
- Q45 medium
Variance is expressed in
💡 Explanation:Squaring deviations changes units (e.g., cm²).
- Q46 easy
Range is most affected by
💡 Explanation:A single outlier can greatly widen range.
- Q47 easy
If IQR = 12, semi-interquartile range (quartile deviation) is
💡 Explanation:12/2 = 6.
- Q48 hard
For Q1 = 10, Q2 = 20, Q3 = 30, Bowley skewness is
💡 Explanation:(30+10−2×20)/(30−10) = 0/20 = 0 (symmetric).
- Q49 hard
The third central moment is related to
💡 Explanation:Skewness builds on the third standardized moment.
- Q50 hard
The fourth central moment is related to
💡 Explanation:Kurtosis uses the fourth standardized moment.
- Q51 hard
By Chebyshev, at least what fraction lies within 4 SD of the mean
💡 Explanation:1 − 1/16 = 15/16 = 93.75%.
- Q52 easy
Positive skewness means
💡 Explanation:Right-skew pulls mean upward.
- Q53 easy
Skewness measures
💡 Explanation:Skew indicates tail direction.
- Q54 medium
The second moment about the mean (average squared deviation) is
💡 Explanation:Second central moment is variance.
- Q55 medium
The first moment about the mean is always
💡 Explanation:Σ(x − mean) = 0.
- Q56 Past Paper · PPSC/FPSC/CSS medium
Multiplying every value by 3 multiplies standard deviation by
💡 Explanation:Scaling multiplies SD by |constant|.
- Q57 Past Paper · PPSC/FPSC/CSS medium
Adding a constant to every value changes standard deviation by
💡 Explanation:Shift does not affect spread.
- Q58 Past Paper · PPSC/FPSC/CSS easy
Interquartile range equals
💡 Explanation:IQR is spread of middle 50%.
- Q59 Past Paper · PPSC/FPSC/CSS easy
If Q1 = 20 and Q3 = 40, quartile deviation is
💡 Explanation:(40−20)/2 = 10.
- Q60 hard
Mean deviation from the median for 1, 3, 9 is
💡 Explanation:Median = 3; |1−3|+|3−3|+|9−3| = 8; MD = 8/3.