Monday October 19 2015 Tuesday October 20 2015
Monday October 19, 2015 Tuesday October 20, 2015 Unit Question What role do the forces in the world play around us? Guiding Question / Learning Target Strengthen ability to read and create graphs. Warm-up Why should you include graphs in lab write-ups? One more way to explain data! Easy way to see relationships. Agenda 1. Graphing notes and practice Homework 1. Quiz retakes during AT! 2. Quiz next class
Graphing Notes Tables, charts and graphs are convenient ways to clearly show your data.
• The cafeteria wanted to collect data on how much milk was sold in 1 week. • The table below shows the results. • We are going to take this data and display it in 3 different types of graphs.
Types of Variables in Graphing Manipulated/Independent Variable: The variable that the experimenter changes Responding/Dependent Variable: The variable that is observed (the one that changes in response to the manipulated variable)
There are three basic graph forms. üNotice how each of the following examples are used to illustrate the data. üChoose the best graph form to express your results.
Bar Graph A bar graph is used to show relationships between groups. The two items being compared do not need to affect each other. It's a fast way to show big differences. Notice how easy it is to read a bar graph.
Circle Graph or Pie Chart A circle graph is used to show a part of something relates to the whole. This kind of graph is needed to show percentages effectively.
Line Graph A line graph is used to show continuing data; how one thing is affected by another. It's clear to see how things are going by the rises and falls a line graph shows.
Scale notes for line graphs Choose the right scale for the axis Must be consistent (same spacing) Must include all data Zero isn’t always data! Choose increments that make it easy to read and place numbers. If my data is. 1 through. 3 I don’t want to count by 10’s!
Bar Graph The same data displayed in 3 different types of graphs. Circle (Pie) Graph Line Graph
On what day did they sell the most chocolate milk? a. Tuesday b. Friday c. Wednesday
On what day was the least amount of chocolate milk sold? a. Monday b. Tuesday c. Thursday
On what day did they have a drop in chocolate milk sales? a. Thursday b. Tuesday c. Monday
Choosing the Right Graph Use a bar graph if you are not looking for trends (or patterns) over time; and the items (or categories) are not parts of a whole. • Use a pie chart if you need to compare different parts of a whole, there is no time involved and there are not too many items (or categories). • Use a line graph if you need to see how a quantity has changed over time. Line graphs enable us to find trends (or patterns) over time.
What are the two tricks to go from a data table to a graph? Dependent Responding Y - axis Manipulated Independent X - axis OR
Graph Y Graph X And the your bottom is your Take Rotate it 90* data graph’s table X, the side, Y Left
To go from a table to a graph remember DRY MIX Rotate your table 90*. The Row on the bottom becomes your X axis, the Columns up the side your Y. TURN YOUR PAPER BACK BEFORE YOU CONSTRUCT YOUR GRAPH!
Making a Graph Always include: Title X-axis labels and y-axis labels The axis of the graph has consistent spacing.
Types of Relationships in Graphs
Direct Relationship When values on two variables tend to go in the same direction, we call this a direct relationship. The correlation between children’s ages and heights is a direct relationship. That is, older children tend to be taller than younger children. This is a direct relationship because children with higher ages tend to have higher heights.
Inverse Relationship When values on two variables tend to go in opposite directions, we call this an inverse relationship. The correlation between students’ number of absences and level of achievement is an inverse relationship. That is, students who are absent more often tend to have lower achievement. This is an inverse relationship because children with higher numbers of absences tend to have lower achievement scores.
What kind of relationship? Direct Inverse
Grades Effort vs. Grades Effort What kind of relationship? Direct Inverse
Is there a relationship? NO!
No Relationship: Data is in a random pattern. There is no relationship or cause and effect between variables.
Recap: What is a relationship? A connection! What does a line going up represent? A direct relationship What does a line going down represent? An inverse relationship Does every graph or all data show a relationship? NO! It depends on the shape of the graph!
Exit Questions You want to make a graph showing how you spend your day, such as sleeping, school, tv, etc. What is the best type of graph to use?
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