Methods of Data Presentation

A comprehensive collection of vocabulary flashcards covering textual, tabular, and graphical methods of statistical data presentation based on the lecture material.

Textual Presentation

A method of presenting data where important figures or highlights of the study are incorporated directly into the text or a paragraph of a report.

Tabular Presentation

The systematic organization and arrangement of figures in rows and columns for easy reading, analysis, and comparison of relationships among variables.

Formal Statistical Table

A systematic table containing all essential structural parts—including the table number, table title, head note, stub head, box head, column headings, footnotes, and source notes—that can stand alone without an introductory statement.

Table Spanner

A heading in a statistical table that covers the entire table body.

Frequency Distribution Table

A tabular arrangement of data formed by grouping values into mutually exclusive classes and displaying the number of observations falling into each class.

Single-Value Grouping Frequency Distribution Table

A form of frequency distribution where distinct individual values serve as the classes; commonly used for qualitative data.

Grouping by Class Intervals

A form of frequency distribution where mutually exclusive classes are defined in the form of intervals; used for quantitative data.

Range ($R$)

The difference between the highest observed value and the lowest observed value in a data set: $\text{highest observed value}-\text{lowest observed value}$ .

Sturge's Formula

A rule used to determine an adequate number of classes ($k$) for a data set of $N$ observations: $k = 1 + 3.322\log(N)$, rounded to the nearest integer.

Class Width or Size ($c$)

The width of each class interval, obtained by calculating the ratio $c^* = \frac{R}{k}$ and rounding up $c^*$ to the nearest value with the same precision as the raw data.

Class Boundaries (CB)

Numbers that fall halfway between the upper limit of a class and the lower limit of the next class.

Class Mark or Class Midpoint (CM)

The average of the lower limit and upper limit of a given class interval.

Relative Frequency (RF)

The proportion of total observations belonging to a class, obtained by dividing the frequency of that class by the total number of observations.

Relative Percentage

The percentage share of a class relative to the whole, obtained by multiplying the relative frequency by $100\%$.

Cumulative Frequency (CF)

The accumulated frequency of observations associated with a class interval.

"Less Than" Cumulative Frequency ($<CF$)

The total number of observations whose values do not exceed the upper limit of a given class.

"Greater Than" Cumulative Frequency ($>CF$)

The total number of observations whose values are not less than the lower limit of a given class.

Graph

A device for displaying numerical values or relationships in pictorial form.

Frequency Histogram

A graphical representation showing the overall shape of a distribution using adjacent vertical bars with no gaps, where bar height equals class frequency and bar width represents class size.

Modal Class

The class interval with the largest class frequency, represented by the tallest vertical bar in a frequency histogram.

Frequency Polygon

A line graph constructed by plotting class frequencies at the midpoints of the classes, connecting the points with straight lines, and closing both ends with two additional classes.

Line Chart

A graphical presentation suitable for time series data that emphasizes movement over time to display trends, patterns, and forecasts.

Column Chart

A chart using vertical bars where height represents magnitude for specific categories or time periods, with a vertical scale starting at zero.

Horizontal Bar Chart

A chart used for qualitative data across a specific period of time that places categories on the vertical axis and amounts on the horizontal axis to compare magnitudes.

Pie Chart

A circular chart divided into sections representing component parts of a total percentage distribution, best suited for data sets with fewer than $6$ categories.

Pictograph

A graphical display that uses self-explanatory symbols to represent numbers and approximate figures, primarily used to attract reader attention.

Statistical Map

A cross-hatched or shaded map that displays numerical data—such as rates, counts, ratios, percentages, or indices—across geographical areas.

Stem-and-Leaf Display

A data presentation device introduced by Tukey in $1977$ that separates each numerical measurements, ordering the leaves from lowest to highest beside each stem and providing a key.