Problem Statement
A properly written problem statement is to include various parts and should be written as a question. Refer to the following problem statement as you develop your own.
What effect does the amount of water (5mL, 10 mL, 20mL, 50 mL) added each day to Phaseolus vulgaris L. (kidney bean plants) have on the overall growth (height, health [color], number of leaves, branches, flowers, and fruit) over a 60 day period of time?
A properly written problem statement will begin with the statement: “What effect does ____ have on ______” This wording requires an explanation and can not be answered with a “yes” or “no”.
The first blank is where you would write your manipulated variable, or the thing that you are changing to see what effect it has. In my case it is the amount of water added each day to see what effect it will have on the growth of kidney bean plants. You need to be specific and identify the various MV’s that you will be testing. In my case I will be adding 5mL, 10mL, 20mL, and 50mL to different groups to see the effect.
I also included other parameters that a reader would need to know when I stated that these various amounts of water would be added. If you add too much water too soon, the seed may rot and never begin to grow.
If possible you should state the scientific name of the plant or animal that you plan on using in your experiment, properly spelled with genus and species followed by the common name the plant or animal is known by in the world, written in parentheses as in Phaseolus vulgaris L. (kidney bean plants).
Your responding variables are then added on the second blank so that your reader is aware of what it is that you will be measuring to determine the effect.
In my example above this would be “overall growth (height, health [color], number of leaves, branches, flowers, and fruit)”
Note that the word “growth” needs to be specified. There are various ways to determine growth and they should be stated so that the reader will know exactly what you will be looking for in your experiment as in “(height, health[color], number of leaves, branches, flowers, and fruit)”
Finally you should conclude with a statement of the amount of time that you anticipate collecting your data for your experiment, as in our case: “over a 60 day period of time”.
Using my problem statement as an example we could vary the manipulated variables as follows if we wanted to know what affect the type of soil would have on the growth of my kidney bean plants. It would look something like this:
Examples
1. What affect does the type of soil (Composted, Professional Potting Soil, White Sand, or dirt) have on the average growth (height, health [color], number of leaves, branches, flowers, and fruit) of a Phaseolus vulgaris L. (kidney bean plant) over a 60 day period of time?
2. What affect does the amount of water (10ml, 20ml, 30ml, or 50ml ) per day have on the average growth (height, health [color], number of leaves, branches, flowers, and fruit) of a Phaseolus vulgaris L. (kidney bean plant) over a 60 day period of time?
3. What affect does the type of liquid fertilizer (Miracle Grow, Peters Professional, or Nature’s Own) added two weeks after germination have on the average growth (height, health [color], number of leaves, branches, flowers, and fruit) of a Phaseolus vulgaris L. (kidney bean plant) over a 60 day period of time?