1. Warm Up Work silently. Your homework should be on your desk. Ask Ms. H questions when she comes to your desk Answers must be in COMPLETE SENTENCES. John believes younger students can finish puzzles quicker. Students in elementary school, middle school, and high school were given a puzzle to assemble. The puzzle assembly time was measured. 1. Identify the independent variable. Explain your choice. 2. Identify the dependent variable. Explain your choice.

2. Graphing! Objective: I will be able to organize data in a graph and table

3. Graphing Skill #1: What Type of Graph is it? Pie Bar Histogram Line Scatterplot

6. Line Graph

7. Graphing Skill #2: Labeling Axes The independent (manipulated) variable is written along the horizontal axis (X axis) Dependent (responding) variable is written along the vertical axis (Y axis) Units on any variables should be included in parentheses ( ) following the axis title

8. Graphing Skill #3: Scaling Axes Range = largest #- smallest # Range /# of intervals

9. Find the Range of your Data  For each variable range = largest value – smallest value Day range= 20-0=20 Height range=12- 0=12 DayHeight (cm) 00 56 87 108 2012

10. Find How Many Marks How many marks are on each axis? –Count the marks Y axis=12 X axis=10

11. Divide Range by # of Marks Y-axis 12/12= 1 X-axis 20/10= 2 If the answer is a decimal choose a number close to that number (larger if possible). That number is how much each mark is equal to on that axis.

12. Mark the scale you chose

13. Graphing Skill #4: Plotting Points STEP 1: Select the first pair of values from the data table (X and Y). STEP 2: Draw a light dashed line up from the number on the X axis and over from the number on Y axis. o Once you get good at plotting points, you won’t need to draw these lines anymore STEP 3: Where these dotted lines cross, put a dark point. Repeat for the next pair of points.

14. Graphing Skill #5: Best-Fit Line or Curve Do you notice a pattern or trend in the data? If so, draw a straight line or curve that represents that trend. All points should lie on or very near the line For points not on the line, about half should be above the line and half below the line o The sum of the distance between the line and all points above should approximate the sum of the distance between the line and all points below (residual values) Your line should not extend beyond the range of your data

15. For bar graphs… Draw a bar up from the X axis point to the Y axis point Repeat for each separate data point

16. Graphing Skill #6: Creating Titles Must communicate the dependent and independent variables Can be presented in the form “Y versus X” Some graphs need more explanation than others. Make sure your reader would be able to understand what your data represent

17. Data Tables! Also organize information Doesn’t matter where independent v dependent goes We will do this: Independent variable labels rows Results of each trial (dependent variable measurement) go on columns

18. Corn produced % Nitroge n in soil Trial 1Trial 2Trial 3Trial 4Average 106748 1520152030 2040503060

19. What are trials? When we do the same step in an experiment several times Why? Want to cancel out effects of error/mistakes So we take average (or mean) of trials

20. Average (Sum of all data points)/(# of data points) Ex: Corn produced: 6, 7, 5, 8 Average = (6+5+7+8)/4 = 6.5

21. Corn produced % Nitroge n in soil Trial 1Trial 2Trial 3Trial 4Average 1067586.5 152010203020 4050306055

22. Homework Graphing practice sheet

23. Daily Quiz Work silently Will grade when time is called

24. Daily Quiz Answers Remember the 6 steps: Is there a title? Are axes labeled? Is the scale appropriate? Are points plotted correctly? Is there a line connecting them? Give a score out of 5. Top Ten: how’d we do?