Review of 6th grade material to help with new Statistics unit Statistics Review Review of 6th grade material to help with new Statistics unit

Vocab Mean Average of a set of numbers Median Middle value of a set of numbers, put in order Mode number(s) that occur the most often Range distance from largest to smallest Frequency table Using tallies to count occurrence of a number or event Stem and Leaf Plot Another way to organize numbers using ones place and tens place Dot Plot Represent data on a number line

Vocab Line Plot similar to a dot plot using x’s Bar Graph represent categorical data Histogram represent ranges of data Box and Whisker Plot uses 5 number summary to divide up data into quarters Interquartile Range middle 50% of data, broken up using quartiles MAD Mean Absolute Deviation, average distance between each data value

Mean, Median, Mode, Range How do you calculate each? Is one better than the other How do they change when data is added.

Example Find the Mean, Median, Mode and Range of the given set of numbers 2,2,7,8,5,4,4,3,2,9,9,8,7,6,6,1,3,4,8,7,7,5,2 What would happen if we add another number? Does the number we add make a difference?

Types of Data Numerical Data data that is measureable, time, height age Categorical Data represent characteristics of something, gender, color, favorite food Each can be used in different situations and different types of graphs

Collection Data Frequency Table Make a 3 column table 1st column is the choice of height, could be a range of numbers 2nd column Is the tally marks for each time you see that data point 3rd column is the sum of the tally marks Stem and Leaf Plot T chart with 10s place on the left and ones place on the right

Example Make a frequency chart for the following students heights in inches 58,62,60,56,55,58,60,60,62,59,62,58,56,59,62,60 Make a Stem and Leaf plot of the following data 12,15,22,26,34,17,45,33,41,22

Types of Graphs Dot Plot Represent number of data points above a number line using circles Line Plot similar to a dot plot but with x’s Bar Graph Usually use categorical data, hiehg of bar represents frequency Histogram Represents ranges of data and then has a bar to represent frequency How to come up with the ranges Box and Whisker Plot a 5 number summary dividing the data into 4 parts that each represent the same percentage of data, not the same space

Example Box and Whisker

Examples

MAD and Interquartile Ranges Calculate the mean Find the difference between the mean and each data point Find the absolute value of each difference Find the average of the absolute values Interquartile Range The box in a box and whisker plot Order data least to highest Find the median Find the median of the upper half of the data Find the median of the lower half of the data Find the different between the upper and lower means

Examples Calculate MAD 5,12,19,4,23,33 Calculate the Interquartile Range 6,12,8,15,9,7

Interpreting Graphs Reading information from a graph Answering Questions based on the graph and graph type

Example What type of side if any was ordered more than 24 times? What type of side was ordered the least? What is the absolute difference in the number of pies and shakes ordered? How many pies were ordered? In total how many sides were ordered that day at the diner?

How many coins were collected in 2013? Did number of coins collected increase or decrease between 2012 and 2013? Which year had the greatest number of coins collected?

What was the highest test score? What percent of class is above a 72? What is the median score? Do you think this test was too hard for the students? Explain. Would you expect the mean to be above or below the median? Explain.