Statistics allows the presentation of figures and facts in a way or form that is define. This helps make it logical and more concrete then just describing. It consolidates the whole groups of figures into one figure. It also simplifies the data. The raw data on its own can confusing and seem incomplete. By using different measurements in statistics such as average, graphs, correlation; the data then becomes more simplified. These different measurements help interpret and infer drawings. When the data is simplified and presented in an easier form such as graphs, comparison becomes easier as well. Comparison is an important function in statistics. ...view middle of the document...
Now, comparison is not the only function there is also the formulation and testing of the hypothesis and this is very important as well. Statistics helps develop new theories by examining the truth, it helps innovate new ideas.
For example, many administrators, economist and scientist amongst more use statistics to help formulate policies, plans and programs by using and analyzing data and this data helps as well to forecast trends and tendencies. It also allows to predict the variable and values of the future. For example, an entrepreneur can forecast the projections of his sales basing it on the present demand and his experiences with the sale in his past. Also, by using the evidence presented in a simplified form with statistics and reasoning, enables the process of inferring something and coming up with a conclusion that is logical and comes from accepted propositions presented.
The Standard Deviation is a measure of how spread out numbers are.
Its symbol is σ (the greek letter sigma)
The formula is easy: it is the square root of the Variance. So now you ask, "What is the Variance?"
The Variance is defined as:
The average of the squared differences from the Mean.
To calculate the variance follow these steps:
* Work out the Mean (the simple average of the numbers)
* Then for each number: subtract the Mean and square the result (the squared difference).
* Then work out the average of those squared differences. (Why Square?)