Paper B Example Topic

Syllabus Reference: 9.4.4 Graphical Presentations

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Bar charts are useful for presenting categorical data. They consist of rectangular bars, where the length of each bar represents the frequency or proportion of a category. For example, a bar chart could be used to show the number of patients in different age groups or the proportion of patients who received a particular treatment. Bar charts are easy to read and can quickly convey information about the distribution of categorical variables.

Histograms are similar to bar charts but are used to display continuous data. They consist of a series of adjacent rectangles, where the height of each rectangle represents the frequency or proportion of data points within a particular range of values. For example, a histogram could be used to show the distribution of blood pressure measurements in a population or the distribution of lengths of hospital stay. Histograms are useful for identifying patterns in continuous data and can be used to assess normality and identify outliers.

Pie charts are another common graphical presentation used for displaying categorical data. They consist of a circle divided into sectors, where the area of each sector represents the frequency or proportion of a category. Pie charts are useful for displaying proportions and percentages, but they can be difficult to read when there are too many categories.

Scatter plots are used to display the relationship between two continuous variables. They consist of a series of points, where each point represents the value of the two variables for a particular observation. Scatter plots can be used to identify patterns in the data, such as positive or negative correlations, or to identify outliers.

Box plots, also known as box-and-whisker plots, are used to display the distribution of continuous data. They consist of a box with whiskers that extend to the minimum and maximum values of the data. The box represents the interquartile range, while the line in the box represents the median. Box plots are useful for identifying the spread of the data, as well as the presence of outliers.