Presenting Data

Make a data table

• Your data table should include– Descriptive title that includes both the independent

& dependent variable– Labels & Units for all Columns and rows

• NO units in raw data

– Repeated Trials – Data should all have the small number of decimal

places.– Averages – Standard deviations

Example TableOxygen Gas Production (ppm)

Uncertainty 0.+/-001ppm

Low Light Intensity

Medium Light High Light

Trial 1 2000.00 4000.00 6000.00

Trial 2 2225.00 4232.15 6234.77

Trial 3 1599.22 3876.11 5987.22

Average 2000.00 4000.00 5000.00

Standard Deviation

10.55 30.33 15.00

Habitat Thickness (mm) of shells of the snail Littorina obtusata MeanStandard deviation

With Crabs

1.02 0.88 0.75 0.83 0.86 0.93 0.91 1.05 0.895833333

0.093074587

Without Crabs

0.71 0.78 0.55 0.33 0.36 0.82 0.62 0.540.5675

0.154397657

Graphing Data

• All Graphs need a descriptive Title• Label both axes with SI units if appropriate.

NO NAKED NUMBERS.• Axes should have an appropriate scale,

decided by the highest and lowest number.• Independent Variable belongs on the X-axis• Dependent Variable belongs on the Y-axis.

Types of Graphs:

• Bar Graphs• Line Graphs• X & Y Scatter Plot Graphs• Pie Charts• Histograms

Bar Graphs• Bar graphs are designed to make comparisons

of data. • The data represented in bar graphs are not

necessarily dependent on any other variables and the groupings are usually qualitative.

• These are best used to show numeric data that represent discrete items or experiments.

• Bars imply that there are no intermediate values.

Bar Graph

Bar graph example

Line Graphs Track a Change over time

• Line graphs are used to track changes over short and long periods of time.

• Line graphs can also be used to compare changes over the same period of time for more than one group.

Line Graph Example

• Notice that time is always on the X-axis

X-Y Scatter Plot

• Shows the relationship between two measured variables as a scatter of individual points, each representing an item with its position determined along the X and Y axes by its values for the two variables.

• . The points of a scatterplot are never connected by lines, but instead a regression line/ best fit line is often plotted, showing how one measurement varies in relation to the other

X-Y Scatter Plot

• This could be comparing the diameter of a tree compare to the length of a tree

Pie Charts

• Pie charts are designed to show a percent of a whole, where the whole equals 100%.