Topic 5 · Statistics & Probability
Grouped Data & Sampling
Averages and range from grouped frequency tables, and how to take a fair sample.
By the end of this topic you can…
- Find the modal class and estimate the mean of grouped data
- Estimate the range from a grouped frequency table
- Choose an appropriate sampling method and spot bias
Lessons
- The Mean and Range from Grouped Data Using midpoints to estimate the mean of a grouped frequency table, and estimating the range from the class boundaries.
- The Modal Class and the Median Class Finding the class with the highest frequency and the class that contains the median, and seeing how regrouping can change them.
- Sampling and Bias Planning a survey: primary or secondary data, quantitative or qualitative, sample size, and how bias creeps in.
Grouped data and sampling quiz
Ten questions drawn at random from a bank of thirteen, covering the estimated mean, modal and median classes, the estimated range, and fair sampling. A calculator is allowed.
10 questions · pass mark 70%