GRAPHS
Ordered pairs: find them
Sampling • Survey questioning- When finding a sample group we want to find one that does not lean towards a certain answer. • There are two types of groups Bias- would lean towards a certain choiceNot a good group as it is influenced by their opinion. Unbias- a good mixture of people who may or may not agree. A good group that samples the general public.
Analyzing scatterplots • Scatter plots are used to find the relationships between 2 things. • HOW DO YOU DESCRIBE IT? You then draw a line up the middle of the direction they are going • Using the labels on the X and Y axis describe what you see ANS:?
Creating scatter plots Mr. Oliver asked kids how long they studied for a test….
Hours of study
Strategy Label the X and Y axis using the sides of the T-chart Use T-charts and graph ordered pairs
1h. 2h. 3h. 4h. 5h.
Grade percentage
34% 44% 25% 33% 25% 66% 77% 50% 73% 66% 88% 68% 88% 82% 93% 85% 66% 90% 99% 93%
Analyzing Line plots • Line plots allow us to find out how often a certain event number or event happens
Line plots allow us to find: Mean- Average-All scores added and divided by number of total scores Mode-Most common Median- Middle score Range- High-low scores and distance between them
Creating Line plots • Jeff polled the class to see how many pets they owned. Below are the results. 3 4 0 2 3 4 2 1 2 0 2 3 1 3 3 2 Strategy: Just put an x above each number
0
1
2
Mean? Mode? Median? Ramge?
3
4
Analyzing double bar • Double bar graphs are used to compare 2 different groups and how they respond to questions differently • A colour key helps us to read it •Common phrases More- compares one set of bars to another Most- means more then 50% Many - a lot Less then- lower amount Majority- over 50% of a certain colour or group Minority- lowest set or group
Creating double bar graphs Keane is comparing favourate shows for boys and girls. Here are his results. Create a double bar for him using this information. GIRLS III Soaps Cooking IIII II Reality I News Cartoons III
BOYS II I IIIII I IIIII
• STRATEGY: Give it a title on top Label bottom with what is being compared Create a colour key for each group Use the Y axies to show amount Fill in bars
Analyzing histograms • Histograms are like single double bar graphs. • They measure frequency or how often a certain occurrence happens over a particular range
They are read similar to Line plots
Creating a Histogram • Mack is recording the size of trees outside. She needs to create a histogram to compare the frequency of tree sizes Diameter of trees Number like that
20-50 cm 51- 70 cm 71- 90 cm 91- 110 cm
IIII III IIII
III IIII IIII II
Strategy • List your frequencies on the x axis 1) List your amounts on the y axis 2) Top your bar up to that level
Analyzing Stem Leaf Plots • In a stem-and-leaf plot each data value is split into a "stem" and a "leaf". The "leaf" is usually the last digit of the number and the other digits to the left of the "leaf" form the "stem". The numbers: • 19,22,25,26,27,28,29,30,34,3 6,37,42,43,44,46,48,48,49,52, 53,55,57,58,62 • would be split as:
We also can find : •Mean •Mode •Median •Range
Creating Stem Leaf plots
• Mean: average- add all numbers and divide by the total number of numbers added • Mode- what number shows up the most times • Median: the middle score
Percentage and pie graphs Imagine Norman asked 800 people what their their favourate movie. How many liked each type?
• We can use ratios and equivalent ratios to solve pie graphs with totals over 100