Yet there is considerable opposition to the use of genetically modified plants for food production and other uses. Genetic engineering offers a time-saving method for producing larger, higher-quality crops with less effort and expense. You are a tomato farmer whose crops are threatened by a persistent species of beetle. 2  Each year, you spend large sums of money for pesticides to protect your crops.
To calculate the variance follow these steps: 1  Work out the Mean (the simple average of the numbers). 2  Then for each number: subtract the Mean and square the result (the squared difference). 3  Then work out the average of those squared differences.
Example: To find the Standard deviation of the data set: 3,2,4,1,4,4. Step 1: Calculate the mean and deviation. uniform, then the standard deviation will be small. indicating that there is a wide variance in the responses, then the standard deviation will be large.