Practical investigations
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I am currently analysing the results of my Vitamin C and peppers investigation. As part of my analysis, I want to show that there is a significant difference between the Vitamin C content of the red, yellow and green peppers. I tried working out the standard deviation and standard error to plot onto a bar-chart (to see if there is overlap in the lines, and hence any difference), but the numbers were so small it’s almost impossible to draw the lines. Could you recommend a statistical test which I could use as part of my analysis? 260308
Igloo writes ...
What you have been doing statistically with your results seems fine to me. The problem is that almost certainly the difference in the vitamin C contents of the three different types of peppers happens to be insignificant, and no amount of juggling around with the figures is going to alter this.
When I carried out a similar investigation I came to the conclusion that any difference has far more to do with the age of the pepper (i.e. how ripe it is), and its horticultural variety as to whether it’s red, yellow or green in colour. Did you consider these other factors as well? If not, your conclusions are not as valid as they could be.
Risk assessment
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updated: 28 March 2008
