Topic 4.2 - Cumulative Frequency Graphs and boxplots

Front

What is a cumulative frequency graph?

Back

A cumulative frequency graph is a graphical representation that shows the cumulative frequency of data points in a dataset, allowing for the visualization of how many data points fall below a certain value.

Front

How do you find the median from a cumulative frequency graph?

Back

To find the median, locate the point on the cumulative frequency graph where the cumulative frequency is half of the total number of data points.

Front

What does the interquartile range (IQR) represent?

Back

The interquartile range (IQR) represents the range of the middle 50% of a dataset, calculated as the difference between the upper quartile (Q3) and lower quartile (Q1).

Front

How do you calculate the IQR?

Back

IQR = Q3 - Q1, where Q3 is the upper quartile and Q1 is the lower quartile.

Front

What is a boxplot?

Back

A boxplot is a standardized way of displaying the distribution of data based on a five-number summary: minimum, first quartile (Q1), median, third quartile (Q3), and maximum.

Front

What does the upper quartile (Q3) represent?

Back

The upper quartile (Q3) represents the value below which 75% of the data points fall.

Front

What is the lower quartile (Q1)?

Back

The lower quartile (Q1) is the value below which 25% of the data points fall.

Front

How do you interpret the whiskers in a boxplot?

Back

The whiskers in a boxplot extend from the quartiles to the minimum and maximum values, indicating the range of the data.

Front

What is the purpose of a cumulative frequency table?

Back

A cumulative frequency table summarizes data by showing the cumulative total of frequencies up to each value, helping to identify medians and quartiles.

Front

How can you determine the number of students scoring below a certain percentage using a cumulative frequency graph?

Back

By locating the percentage on the x-axis and reading the corresponding cumulative frequency on the y-axis.