Chapter 1: The Nature of Science

 Identify three types of graphs and explain the ways they are used.  Distinguish between dependent and independent variables.  Analyze data using the various types of graphs.

 Graph: a visual display of information or data.  Make it easier to understand patterns by displaying data in a visual manner.

y-axis x-axis Dependent Variable Independent Variable

 Line graphs show any relationship where the dependent variable changes due to a change in the independent variable.  Often show how a relationship between variables changes over time.

 You can show more than one event on the same graph as long as the relationship between the variables is identical.

 Constructing Line Graphs:  Choose appropriate scale  x-axis should always show the independent variable  y-axis should always show the dependent variable

 Bar graphs are useful for comparing information collected by counting.  Each bar represents a quantity counted at a particular time.  Independent variable is plotted on x-axis  Dependent variable is plotted on y-axis

 Circle graphs, or pie graphs, are used to show how some fixed quantity is broken down into parts.  Each part of the circle graph represents a percentage of the whole.

 Which type of graph would best represent the results of a survey of 144 people where 75 ride a bus, 45 drive cars, 15 carpool, and 9 walk to work?