Mean absolute deviation means the mean distance of the numbers from their mean. It basically tells you how far are the numbers, on average, from the mean of the data.
Here is the video on how to calculate the mean absolute deviation on a calculator to accompany the notes.
Below is a shortened version of the directions from the video on finding the M.A.D.
The website here has a good explanation of how to find the M.A.D. by hand.
This video is a quick review of box plots.
Here is the video that is accompanied by the notes given in class.
Examples are shown below.
Reviewed how to read a box plot as well. Practice here.
What is the highest score?
What is the lowest score?
What percent of people scored between a 73 and 90?
What percent of people scored between an 81 and 90?
What percent of people scored lower than an 81?
What percent of people scored lower than a 54?
Determine whether a sample is a good fit for a statistical question or not.
What factors affect this?
Statistical question - a question that gives variability in its responses
Categorical data - quantitative data, based on categories using words, "What" type of questions
Numerical data - qualitative data, based on numbers, "How many" type of questions
Population - a group of people that is targeted for collecting data from a statistical question
Sample - a smaller group of people within the population that accurately represents the population
Bias - different types of bias will lead to the data being inaccurate for the population
Sample bias - collecting data from a sample that does not match the population
Leading question bias - phrasing a question in a way to elicit a specific response
Undercoverage/non response bias - not asking enough people or getting too few responses
Representative - data that accurately depicts the population based on the sample
Sampling method - a way that is used to select a sample, how is the sample chosen?
Random sample - the best way to reduce bias when choosing a sample