Showing patterns & trends Easily display results Graphing Your Data Showing patterns & trends Easily display results A picture is worth a thousand words!

Types of data Variables Dependent variable what you measure in an experiment we don’t know how it will change until we do the experiment Graphed on the Y- axis Independent Variable: Changed on purpose: it is what is being tested Graphed on the X-Axis 2005-2006

Examples of Experiments 1 How does fertilizer affect the growth rate of plants? we set up an experiment testing different amounts of fertilizer on different plants & measuring the growth (height) of the plants: What is the independent variable (X-axis)? Fertilizer What is the dependent variable (Y-axis)? Growth/height

Examples of Experiments 2 How does exercise affect heart rate of 10th grade student? we set up an experiment testing different lengths of time of exercise (minutes) on the heart rate of students. What is the independent variable (X-axis)? TIME What is the Dependent variable (Y-axis)? Heart rate

Making pictures out of data Graphs line graphs graphing data that shows continuous change bar graphs (or histograms) graphing data that is in disconnected groups How’s a critter to choose?

elevation (feet above sea level) How does elevation affect temperature? Line graph! elevation (feet above sea level) temp. (°C) 30 500 25 1000 20 1500 15 2000 10 2500 5 30 25 20 temperature 15 10 5 500 1000 1500 2000 2500 elevation

Which drink do you like best? number Coke 1 Pepsi Water 4 Iced tea Gatorade 3 6 Bar graph! 5 4 number of students 3 2 1 Coke Pepsi water tea Gatorade type of drink

Rules for Graphing Always use a pencil Independent variable- X axis Dependent variable- Y axis Always put a title on the graph Use an appropriate scale for each axis Create/Use a key if necessary

Any Questions?? 2008-2009