Presentation on theme: "Graphs for Integrated Science"— Presentation transcript:
1 Graphs for Integrated Science Why use a graph?What kinds of graphs are there?How does one make a graph?
2 Why use a graph? Graphs communicate information visually Graphs tell a story –Show patterns and trendsNot language dependentUsed in newspapers, magazines and businesses around the world
3 What kinds of graphs are there? Three types used in integrated scienceBar graphs: a graph drawn using rectangular bars to show size of a valueLine graphs: a graph that uses points connected by lines to show how something changes in valuesPie Charts: percentage data is shown a circle divided like pie pieces.
4 Bar Graphs Bar graphs help compare categories Usually independent variable (factor that differs from group to group) make up categoriesCategories placed upon horizontal axisCategories often qualitative or discrete values
5 Line Graphs Line graphs help show relationships and predictable laws Data is quantitativeValues are continuousDependent variable is on y axisKey or legend necessary if more than one line
6 Pie Charts Show percentage data Data is quantitative Usually has key/legend to identify categoriesDoesn’t use distinguish type of variable
7 Parts of a graph Title: Appears at the top and describes the graph Axes with labels: Reference line drawn on a graph to show values; usually one vertically (y) and on horizontal (x); define the data graphed; (axis is singular)Scale: uniform tic marks (or categories) that show the value of each interval or square; every square must equal the same amount.Legend/Key: chart to help identify different trials or parts of experiment
8 Parts of a graph Descriptive TITLE SCALE: tic marks (or categories) are uniformly incrementedNote: this graph does not start at 0,0 but starts at (1,0) as the first data is day 1, temp 43.AXES LabelsIndependent variable x-axesDependent variable y-axes
9 What kind of graph should I use? Line or bar? Look at the table of your results:If this column (Independent data) hasOnly certain fixed values, or qualitative categories, use a bar-graph:A continuous range of values, use a line-graph:
10 How do I make a line graph? 1. Draw in the axes and use simple scales.Put the dependent variable on the vertical y-axisPut the independent variable on the horizontal x-axis
11 How do I make a line graph? Draw in the axes and choose simple scales.To find a scale,Find the range (highest value – lowest value)Divide the range by the number of squaresChoose the closest simple values:1 large square = 1 centimeter (1 cm) or1 large square = 2 cm, or 5 cm, or 10 cmNever choose an awkward scale, like 1 square = 3 cm or 7 cmMake tic marks and label the axes
12 How do I make a line graph? Plot the points neatly.To mark the point, use an XxUsually you need 5 or more points for the graph.xxxxxRe-check each one before your next step.
13 How do I make a line graph? Draw the “best fit line”If the points form a straight line… …draw the best straight line through themIf the points form a curve,…draw a free-hand curve of best fit
14 How do I make a line graph? Check OutliersIf a point is not on the line,then it is “an outlier.”Check your equipment & dataTitle the graph using descriptive wordsUse words that tell the reader what the graph is about. For example, “World population growth since 1900.” Often you will use the dependent and independent variables in the title.Title the graph using descriptive wordsUse words that tell the reader what the graph is about. For example, “World population growth since 1900.” Often you will use the dependent and independent variables in the title
15 How do I make a line graph? In summary:Draw in the axes and choose good scales,with the dependent variable on the y-axisPlot the points carefully using an X.Draw a line of best fitusing a ruler for a straight line graph,or draw free-hand for a curved graphCheck outliers.Add a descriptive title to the graph
16 WebographyFree Support for Physics for You. Web. 27 Sept Graphing Scientific Data. Web. 27 Sept Google docs. "Displaying Data in Tables and Graphs." Algebra to Go: a Mathematics Handbook. Wilmington, MA: Great Source Education Group, Print.