Understanding Histograms

I found that many students as well as parents are scared of statistics. As we know histograms is a part of statistics. More over histograms is not frequently studied by students still it is used in wide range of fields. You can say that it is a part of collection of science. Basically histograms is an area diagram. The general mathematical definition of histograms is known as two dimensional frequency density diagram. There are generally 5 types of histograms depending on distributions.



There are some steps which need to follow while constructing a histograms.

1) Take x-axis and y-axis and mark x-axis as class intervals and y-axis as frequencies.

2) If class intervals are given in inclusive form then convert to the exclusive form Because class intervals can not be in inclusive form.

3) Now draw rectangles between class intervals base and corresponding heights of frequencies.

4) As we know the class intervals are on x-axis and frequencies are on y-axis the rectangles will be constructed on each class interval.

5) The height of rectangle is proportional to corresponding frequency if the intervals are equal.

6) The area of rectangle is proportional to corresponding frequency if the intervals are unequal.

Always keep that in mind the histogram is different from bar graph. Bar graph is one dimensional and histogram is two dimensional.

Understanding Histogram is step by step method. Hope the above basic concepts of histogram helps you.

5 Important Hints To Calculate Correlation

It is saying that to understand God's thoughts we must study statistics; they are the measure of his purpose. More over the correlation is one of the methods of statistics which used between two continuous variables. The correlation is a very simple method to interpret the possible linear association. As we know that all the methods can be misused at some aspects similarly correlation can also be misused by some researchers. It has many uses in medical research. In this article we will be highlighting uses and calculation hints of correlation.

1) The very first thing to understate in correlation is its definition. Many students fail to understand the definition. “Correlation is a method of assessing a possible two-way linear association between two continuous variables”. It is also called correlation coefficients is statistics.

2) There are two types of correlation coefficients. First is “Pearson's product moment correlation coefficient” and second is “Spearman's rank correlation coefficient”. Some more other types of correlation are used depends on variables being studied.

3) When the values increase together the correlation is positive otherwise correlation is negative when any one value decreases. For zero value correlation doesn’t exist.

4) Correlation can work for curve data also but it can nicely calculate for straight line data. 

5) A correlation is not causation. It means that the correlation always supports that there could be any other reasons for good or bad correlation of data.

The above hints are helpful to calculate and to understate that the correlation coefficients are used in medical and pair of variables linear relations.