Utility of Chi- Square Test( À2)in Biological Science

Utility of Chi- Square Test( À2)in Biological Science
Research
AlokChantia
Ritu Garg
In any research work, we are interested to know the accuracy of the results, and in this
manner, we use chi-square to know the significance or non-significance of data. The
present paper is an effort to know the use of chi-square in analysis.
Every research-based data shows its frequency, which is in the form of percentage. We
also know the difference between expected and observed frequency of a specific trait, if
both the frequencies are equal. We express it as À2 = 0 and this is known as Chi - Square.
Chi-square is a statistical method, which is used, mainly in biological sciences.
Nowadays, computers have shown their utility but the availability of computer in every
university or research institute is rare. So in that situation, use of chi-square is an
alternative. Chi-square is used in those situations in which we examine homogeneity or
heterogeneity or degree of association of two or more variables for "Goodness of fit".
In an avoidable condition, when a researcher uses this test, he should take some following
precautions.
1) Absolute number should be used.
2) In a group frequency of number should be at least five, while Erik(1971) and Yule
and Candale(1968) explain it should be ten.
3) Frequency distribution expansion should be at least fifty.
Many scholars have given comments on chi-square. According to Fisher(1958) chisquare
is not only for the measurement of magnitude of association but also in the form
significance examination. It is free from all additional hypothesis, for the nature of
association, Lewis and Bank(1964) explained the utility of chi-square as a test of
association. Bradelee(1968) found this test full of errors. According to
Hammerton(1975), if some precautions are taken, this test can be used.
A truth comes through from the comments of the above said social scientists. In this
paper, an effort has been made to see the conditions in which the chi-square test can be
used.
To examine