GRE Data Analysis Guide for Nepali Students

GRE Data Analysis Guide for Nepali Students explains descriptive statistics, tables, graphs, probability, distributions, counting methods, Data Interpretation sets and efficient evidence-based review. The strongest preparation combines exact definitions, diagram or data interpretation, efficient calculation and a final reasonableness check.

Information checked on 24 July 2026 against the current ETS Quantitative Reasoning overview, Math Review, mathematical conventions and POWERPREP information. Confirm test details with ETS before your appointment.

Key facts at a glance

Understand the official data scope

ETS includes descriptive statistics such as mean, median, mode, range, standard deviation, interquartile range, quartiles and percentiles; interpretation of common tables and graphs; elementary and conditional probability; random variables and probability distributions; and counting methods including permutations, combinations and Venn diagrams.

These topics are generally taught in high-school algebra or introductory statistics. Inferential statistics is not tested. The task is to extract, compare and model information accurately, not to perform advanced statistical research.

Read the display before the question

Identify the title, population, categories, axes, units, scale, time period, legend and any notes. Determine whether values are totals, rates, percentages, cumulative counts or estimates.

A visually large bar does not automatically represent a large relative change, especially when an axis does not start at zero. Convert the display into one clear sentence before calculating.

Use tables efficiently

Locate the relevant row and column by label, then confirm the intersection and unit. In a large table, trace with a finger or cursor to avoid shifting one row during calculation.

Do not combine values across categories unless the table definitions permit it. Check whether subtotals overlap and whether percentages use the same denominator.

Interpret line and bar graphs

Line graphs often show change over an ordered variable such as time, while bar graphs compare categories. Distinguish a value from its change and an absolute change from a percent change.

Slope on a data graph describes rate of change within the displayed units. A steeper visual line matters only after checking axis scales.

Read circle graphs and proportions

A circle graph represents parts of a whole. Convert a sector percentage to an amount by multiplying by the total. Convert an amount to a share by dividing by the total.

Confirm that sectors represent mutually exclusive categories and total 100 percent, allowing for stated rounding. Do not compare sector angles across charts with different totals as though they were equal amounts.

Understand the arithmetic mean

The mean equals the sum of values divided by their number. Therefore sum = mean × count. This relationship is often faster than listing unknown values.

A mean is sensitive to extreme values. For combined groups, use total sums and counts; do not average group means unless the group sizes are equal.

Use median, mode and range

Order values before finding the median. With an odd count, use the middle value; with an even count, average the two middle values. The mode is the most frequent value and may be absent or non-unique.

Range equals maximum minus minimum and reflects only extremes. A dataset can change internally without changing its range, median or mode, so determine exactly which statistic the question asks about.

Interpret quartiles and boxplots

Quartiles divide ordered data into four parts, and the interquartile range equals Q3 – Q1. A boxplot displays the median, quartiles and endpoints under the convention supplied.

Compare centre and spread separately. A longer box indicates a larger interquartile range, while whiskers reflect outer portions. Do not infer frequencies from geometric length unless the display states them.

Reason about standard deviation

Standard deviation describes spread around the mean. A dataset whose values cluster tightly around its mean has a smaller standard deviation than one with values farther away.

Adding the same constant to every value shifts the mean but does not change standard deviation. Multiplying every value by a positive factor multiplies the standard deviation by that factor. Use these relationships qualitatively when exact computation is unnecessary.

Understand percentiles

A percentile describes relative position within a distribution, not percent correct. Being at the 80th percentile means performing as well as or better than roughly 80 percent of the relevant group under the stated definition.

Do not subtract percentile ranks as though they were equal measurement intervals. Read the exact context and population before interpreting rank.

Read scatterplots and association

A scatterplot shows paired quantitative values. Look for direction, strength, form, clusters and outliers. A positive association rises overall; a negative association falls overall.

Association does not by itself prove causation. The GRE may ask what the graph supports, so select only conclusions warranted by the data.

Build probability from outcomes

For equally likely outcomes, probability equals favourable outcomes divided by total outcomes. Values range from 0 to 1. The complement rule gives P(not A) = 1 – P(A).

Define the sample space carefully. For repeated trials, ordered outcomes may matter even when the final event description sounds unordered.

Distinguish independent and mutually exclusive events

Independent events do not change each other’s probabilities, so P(A and B) = P(A)P(B). Mutually exclusive events cannot occur together, so their intersection probability is zero.

Nonzero mutually exclusive events are not independent. State the relationship in words before selecting an addition or multiplication rule.

Use conditional probability

Conditional probability restricts the sample space to cases where the given condition occurs. P(A given B) equals P(A and B) divided by P(B), provided P(B) is positive.

A two-way table or tree diagram can make the restricted denominator visible. Recalculate from the conditioned group instead of using the original total.

Apply counting principles

Use the multiplication principle for sequential choices. A permutation counts arrangements where order matters; a combination counts selections where order does not matter.

Before using a formula, ask whether objects are distinct, repetition is allowed and order matters. Small cases can expose overcounting or undercounting.

Use Venn diagrams

For two sets, total in A or B equals total in A plus total in B minus the overlap. Subtracting the intersection once corrects double counting.

Fill the overlap first, then exclusive regions and finally neither. Label whether “or” is inclusive and whether the universal total is known.

Interpret distributions and normal curves

A probability distribution assigns probabilities to possible values of a random variable. Total probability equals 1. For a symmetric distribution, centre relationships may simplify comparison.

When a normal distribution is specified, use only properties or percentages supplied or officially expected in the problem context. Do not import unsupported assumptions into a generic bell-shaped graph.

Approach Data Interpretation sets

A Data Interpretation set uses one table, graph or display for multiple questions. Read the display once carefully, note units and definitions, then return to the exact portion each question needs.

Do not let an earlier answer become an unstated fact for the next question. Each item must be supported by the shared data and its own prompt.

Handle Quantitative Comparison data questions

Compare quantities using exact definitions and every permissible dataset. One valid counterexample can show that the relationship cannot be determined.

Test small constructed datasets when a question gives only a mean, median, range or other summary. Different datasets can share one statistic while differing in another.

Use the calculator selectively

The on-screen calculator helps with totals, division and square roots, but it cannot choose the correct denominator or population. Estimate direction and magnitude before entering values.

Keep sufficient precision when answer choices are close. Check units and convert proportions, decimals and percentages consistently.

Create a data error log

Classify misses as display reading, wrong denominator, mean weighting, ordering, absolute-versus-relative change, probability rule, counting structure, unsupported inference or calculator entry. Record the first bad decision.

Re-solve later and explain the display in one sentence before calculating. Create a small altered table or sample space to test whether the rule transfers. For combined groups, independently reconstruct the total sum from each count and mean before trusting a weighted result.

Practise with official resources

Use the ETS Quantitative Reasoning overview for current scope and response formats. Study the official GRE Math Review for definitions, examples and exercises.

Move from untimed interpretation to mixed timed sections and POWERPREP. Review correct guesses and slow calculations alongside wrong answers.

Follow a seven-step data routine

Read title and units; define the population; identify the required statistic or event; choose the denominator; estimate; calculate; then interpret the result in the original context.

For probability and counting, write the sample space or choice stages before applying a memorised formula.

Connect preparation with applications

For graduate-study planning, documents and destination guidance, visit MKS Education. For structured GRE preparation, explore MKS Prep. Verify current testing requirements with each university.

Use diagnostic evidence to prioritise weak data skills and align testing, score reporting and application deadlines.

Frequently asked questions