Graphing and Analyzing Scientific Data

• Write the following heading in your notebook and answer the bell work question.

• “Graphing and Analyzing Scientific Data”8/26/2015

Homework: Graphing and Analyzing Scientific Data Worksheet (if not finished during class)

BW: Sketch an example of a line graph, bar graph, and pie graph.

Objectives• I will learn about different ways to

graphically represent data. I will also learn how to analyze these graphs for scientific data.

• I will show that I can graphically represent data by constructing my own graphs and using these graphs to analyze a set of given data.

Types of Graphs• Pie/Circle Graphs

• Used to show parts of a whole.

• Bar Graphs• Used to compare amounts

• Line Graphs• Used to show the

change of one piece of information as it relates to another change.

Parts of a Graph • Title

• Summarizes information bing represented in ANY graph.

• Independent Variable• Variable controlled by the

experimenter. Placed on X axis.

• Dependent Variable• Variable directly affected by

independent variable. Placed on Y axis.

• Scales • Tells you where to plot data points.

• Legend• Describes the graph’s data.

Variables

• any item, factor, or condition that can be controlled or changed

• looking for a cause and effect relationship

So then…• x is the …

• y is the…

• m and b are…

• Together they show a…

• Independent variable

• Dependent variable

• Constants

• Relationship

y=mx+b

• Are there any restrictions on what x can be?• What determines the value of y?• What happens when I plug x into that

equation?• Do m and b change?• What is the result if I plug several values for

x into that equation?

Mean, Median, Mode• Mean• Determined by adding all the numbers in a data set together

and then dividing by the number of values. • EX: 2 + 4 + 6 = 12/3 = 4

• Median• Middle number in a set of data. If there is an even set of

numbers in the data, then take the average of the two middle numbers.

• EX: 2, 3, 4, 8, 12, 16, 20 median = 8• EX: 3, 5, 8, 11, 17, 19, 27, 30 median is 11 + 17 = 28/2

• Mode• The number that occurs most often in a data set. • EX: 3, 4, 6, 6, 7, 9, 9, 9, 12, 12, 15 mode = 9

Extrapolate & Interpolate

Interpreting data• Extrapolate: extending the graph,

along the same slope, above or below measured data. What would

you expect pay for 30

Kg?

Interpreting data

• Interpolate: predicting data between two measured points on the graph

Best fit line