Constructing a Graph Unit 1 Most common: Line Graph

1. ID Variables A. Independent Variable i. Goes on the X axis (_________) ii. Should be on ________side of data table. B. Dependent Variable - (changes w/ IV) i. Goes on the Y axis (________) ii. Should be on _______side of data table.

2. Determine Variable Range A. Subtract the lowest data value from the highest data value. B. Do each variable separately.

3.Determine Scale of Graph A. Determine a scale: numerical value for each square, best fits range of each variable B. Spread graph to use MOST available space.

Number and Label Each Axis 1. This tells what data the lines on your graph represent.

Plot the Data Points A. Plot each data value on the graph with a dot. B. You can put the data number by the dot, if it does not clutter your graph.

Draw the Graph A. Draw a curve or a line that best fits the data points. B. Most graphs of experimental data are not drawn as "connect-the- dots".

Title the Graph A. Your title should clearly tell what the graph is about. B. If your graph has more than one set of data, provide a "key" to identify the different lines.

BAR Graphs A. If either dependent (DV) or Independent (IV) variable are NON-numeric (qualitative) B. Used to compare things btwn different groups C. If there is >1 set of data you need to have more than one bar

CIRCLE (PIE) Graphs A. If both DV and IV are NON-numeric B. Use when DV or IV is in % or when comparing PARTS to a WHOLE C. Should be presented in order, largest to smallest, to make it easier to interpret figures

LINE Graphs A. If BOTH DV and IV are numbers (quantitative) B. Show a trend or change over time C. If >1 set of data  you need >1 line

Practice Graphing  Open “Constructing a Graph” PP  Go to slide show  Click here on: Practice Graphing HerePractice Graphing Here

In groups:  Complete Practice Interpreting Data #1-10  Complete Tadpole population A line graph may be made in Microsoft Excel or at Create a GraphCreate a Graph Print Graph and answer the questions