Statistics is part of Mathematics and holds 730 questions with answers, free to read and with no account needed.
Questions from this area appear in PPSC, FPSC and NTS papers. Each guide explains how that paper is built and which subjects carry it.
Attempt each question before revealing the answer, and keep a note of the ones you get wrong — those are the topics worth reading about properly. If an answer looks wrong, there is a link to report it on every question.
Answer: A. Symmetrical
The Student t-distribution features a bell-shaped curve centered symmetrically around zero. Its shape mirrors the normal distribution curve while accounting for smaller sample sizes. Therefore the t-distribution is chara...
Answer: B. Mean
Squaring the deviations from a reference point creates a quadratic mathematical function with a single global minimum. Calculus demonstrates that taking the derivative of this squared error function and setting it to zer...
Answer: A. Mean
Squaring deviations from a central point creates a parabolic error function with a single global minimum. Calculus proves that the sum of squared deviations reaches its absolute minimum at the arithmetic mean. This least...
Answer: B. Contingency table
Contingency tables organize categorical data into intersecting rows and columns for cross-tabulation. Two attributes are analyzed simultaneously to detect potential relationships or frequency associations. Cell frequenci...
Answer: B. Binomial distribution
The binomial distribution models trials conducted with replacement to keep success probabilities constant. Replacing each sampled item ensures previous outcomes do not alter the composition of the population. This consta...
Answer: C. Least
Absolute deviations measure the distance of each data point from a reference point. Mathematical minimization proves that these absolute distances are smallest at the median. Using the mean instead would minimize the sum...
Answer: C. S.D.
The second moment about the mean is defined as the variance, and its square root is the standard deviation.
Answer: B. Mean
Squared deviations measure the distance of data points from a chosen central benchmark value. Calculus demonstrates that the derivative of squared error sums reaches zero at the arithmetic mean. Therefore the sum of squa...
Answer: C. Normal
A normal distribution possesses perfect symmetry around its central arithmetic mean value point. In any perfectly symmetrical distribution, all odd-powered statistical moments calculated about the mean equal zero. This b...
Answer: B. S.D.
A standardized normal variate, commonly called a Z-score, rescales data points into standard units. It measures precisely how many standard deviations a given raw value sits away from the mean. This standardization allow...
Answer: C. Least
The arithmetic mean acts as the unique center of gravity for numerical datasets. Squaring distance deviations ensures positive values that penalize large errors significantly more. Calculus optimization proves that the f...
Answer: D. Class limit
Class limits define the minimum and maximum numerical values that can belong to a frequency interval. These boundary numbers establish where data values are sorted when constructing grouped frequency tables. Lower class...
Answer: A. Mean
The arithmetic mean acts as a mathematical balance point for any dataset. Positive deviations above the mean exactly cancel out negative deviations below it. This balancing property makes the sum of all raw deviations eq...
Answer: C. 1
Binomial trials result in one of two mutually exclusive outcomes labeled success or failure. The variable p denotes success probability while q denotes failure probability. Since all possible outcomes must account for to...
Answer: D. Either of the above
An unusually small number of runs indicates that similar data points are clustered together in long consecutive sequences. An unusually large number of runs indicates that data values alternate back and forth far more th...
