Monday 20 February 2012

Direct indirect measures

Direct and indirect measures in maths for Grade IX:
Direct measure is a measurement of something that we actually want while the indirect measurement is that we are measuring something other than the actual thing of interest.
Let us learn Direct and indirect measures through examples:
Direct measure is looking at actual samples of students’ work produced in the programs organized by the school authority while indirect measurement is gathering information from the sources other than looking at the actual programs those were attained by the students. (know more about cbse sample papers, here)
A direct measurement is counting the number of people those who have entered in a stadium through the gate while the indirect measurement is counting the number of people entering in the stadium with the help of tickets sold from the ticket window. It can be false or not accurate because of all the tickets those that were sold, it is not necessary that they have been used to get entry in the stadium.
If we count the number of students using term papers taken by them by the number of copies then it is the direct measurement. If the number of students is counted on the paper basis then it is indirect measurement because all students may not have taken the exam.
Written surveys and questionnaires are also the examples of indirect measurement.
Let’s have another example. If a person goes to a doctor than he might get a form to fill in which some questions are like:
• Any person in your family affected by cancer.
• Is that person taking medicines like painkiller regularly?
• Is that person is allergenic to anything.
This is like the survey and definitely would not give accurate result. It’s just a measurement or survey that will provide the general information related to the population. A lot people fill these types of forms. So a general percentage can be calculated but it might not be accurate. Accuracy is far away from the result drawn.
In the next session we will discuss about Arc Lengths.

No comments:

Post a Comment