Science Buddies: "Ask an Expert"

Hi To Whom It May Concern:
I need to find out which data analysis would be best for my science fair project. My project is the effect of vitamins on plant growth. Where I had 4 groups of plants 6 plants in each group. Group A was fed with distilled water, group B was fed with water and vitamin B12 in the water, group C got vitamin C, and group D got vitamin E. I have already done my experiment measuring the plants twice a week for 5 weeks. I just need to find out which data analysis would be best for my project.

Charlotte

Hi Charlotte,

Congratulations on progressing so far on your experiment.

How did you measure your plant growth? Height?

You have 6 subjects (N=6) for 4 groups, and you should have 10 measurements per subject (twice weekly per 5 weeks, including baseline).

Depending on what your measurement was, you could do statistical analysis and plot those results in a graph or table.

For example, if you measured height, you could calculate the mean and standard deviation of each group at the end of the study and plot this in a bar graph (to see which group grew the best). You could also plot the mean of each group at each time interval over time (to see how each group grew over time).

Here's a link to help with statistical analysis definitions and calculations:
http://www.cmh.edu/stats/definitions.asp

Here's a helpful link from the Science Buddies "How to do an experiment" toolkit for "Data Analysis and Graph":
https://www.sciencebuddies.org/mentorin ... ysis.shtml
Another great link:
http://www.mathleague.com/help/data/data.htm

Depending on what your hypothesis was, you would want to gear your analysis and how you show your data to demonstrate whether your experiment as proven or disproven your hypothesis.

Hope this helps and good luck!
-Bea