1. Graphing “The basics”

2. The Basics Graphs give us a way to picture data. Basically, graphs provide a picture of a data table. So, what is data? What is a data table?

3. Data Let’s first talk about data. Data is simply information. This information can be about anything… from the height of a person to how much rain fell in a year. The key to looking at this data, is to organize it…

4. Data Table When we make observations and list our data, we often put the information in a data table. A data table is a way of organizing data in columns so it is neat and readable. 100200300400500 2.14.53.41.63.7

5. Data Table Data tables begin with a title which describes the content. Data tables also include variables and units… Student Shoe Size Number of Students 49721 Shoe Size 5 1/2 6 6 1/2 7 7 1/2

6. Variables Variables describe what information is recorded. Variables describe what information is recorded. For example time would be a variable, can you think of other variables?

7. Units Units tell how the variable is measured Units tell how the variable is measured If we used time as a variable, our units could be hours. Can you think of other units we use for time?

8. Ordered Pairs Finally, the information in a data table is organized with ordered pairs. Ordered pairs are two pieces of data directly corresponding to one another. High Temperature During the Weekend DaySaturdaySunday Temperature 75° 78°

9. We might have a temperature of 72°C at a time of 30 seconds. We might have a temperature of 72°C at a time of 30 seconds. Our ordered pair would be 72°C and 30 seconds. Our ordered pair would be 72°C and 30 seconds. Time (seconds) 253035 Temp (°C) 707274 For instance, if we are measuring a change in temperature over a period of time…

10. Types of Variables Ordered pairs consist of independent and dependent variables. Ordered pairs consist of independent and dependent variables. The independent variable “stands alone” and the dependent variable “relies” on the changes in the independent variable. The independent variable “stands alone” and the dependent variable “relies” on the changes in the independent variable.

11. For example, let’s think about the change in temperature throughout the year… So, what is the independent variable in this example? What is the dependent variable in this example? Which variable relies on the other? Which variable stands alone?

12. Independent or Dependent?? Let’s think about this… does time change because of the temperature? Let’s think about this… does time change because of the temperature? No… time doesn’t change because of temperature… it stands alone. No… time doesn’t change because of temperature… it stands alone. Therefore, time is the independent variable!! Therefore, time is the independent variable!!

13. What about Temperature?? Does the change in temperature depend on what time of year it is? Does the change in temperature depend on what time of year it is? YES!! So, temperature is the dependent variable. YES!! So, temperature is the dependent variable. It relies on changes in the independent variable “time”. It relies on changes in the independent variable “time”.

14. Dependent Variables… REMEMBER!! The Dependent variable always relies on changes in the independent variable!!!

15. Tomorrow… Next we will use this information to understand graphs!!!

16. Types We are going to talk about… Line Graphs Bar Graphs Pie Graphs