# Graphing Data.

## Presentation on theme: "Graphing Data."— Presentation transcript:

Graphing Data

OGT Benchmark SI-A Participate in and apply the processes of scientific investigation to create models and to design, conduct, evaluate and communicate the results of these investigations.

OGT Indicator SI-5 Develop oral and written presentations using clear language, accurate data, appropriate graphs, tables, maps and available technology.

OGT Indicator SI-6 Draw logical conclusions based on scientific knowledge and evidence from investigations.

1. Create a data table labeled with units.
Graphing Notes 1. Create a data table labeled with units. Time (s) Distance (m) Red Car Blue Car

2. Decide what type of graph
*Line (scatter) – shows changes over time, relationships or trends

*Bar – compares different things

*Pie (circle) – shows parts or % of a whole thing

3. For line graphs (and bars),. determine the range and scale
3. For line graphs (and bars), determine the range and scale of your variables * range – lowest number to highest number Start at zero if it’s reasonable Example: range of 5 to 50 – start with zero Example: range of 2000 to 3000 – don’t start with zero – most of your graph will be empty space

* scale – labels for each line on the graph
Must be evenly spaced, counting by a reasonable number – 2, 5, 10, 25, 100, etc For line graphs, number the lines, not the spaces Example: - each line is worth 2

3. Label the horizontal axis with the independent variable and its unit – the independent variable is the one you set ahead of time

Label the vertical axis with the dependent variable and its unit – the dependent variable is the one you are testing for Choose a title for your graph. Plot your data points.

8. The graph can then be used to predict unmeasured data points.
Determine the trend in the data – draw a “best fit” line through your data points. 8. The graph can then be used to predict unmeasured data points. * interpolate points within your data range * extrapolate points beyond your data range

Graphing Example Determine the relationship between the number of times a cricket chirps in a minute and the air temperature. Temperature in degrees F # of cricket chirps/min 90 3 80 6 70 11 60 15

*Starting with zero, most of the graph is empty

* With a “best fit” trend line

*Use the graph to interpolate the # of chirps at 75 degrees F.
*Use the graph to extrapolate the # of chirps at 100 degrees F.