In 60 throws of a dice, face one turned up 6 times, face two or three 18 times, face four or five 24 times and face of six 12 times. Test at 10% significance level, if the dice is honest, it being given that P ( 2 > 6.25) = 0.1 for 3 degrees of freedom.
Answers
Answer:
EERING MATHS III
QUSTION BOOK
9
4. The nicotine content in milligrams of two samples of tobacco were found to be
as follows:
Sample
A
24 27 26 21 25
Sample
B
27 30 28 31 22 36
Can it be said that two samples come from normal populations having the same
variances.
Solution:
Calculated F value =4.07
Tabulated Value = 6.26 ( at 5% level of significance with (5,4) degrees of
freedom)
Calculated value < Tabulated value, Accept Ho (Null hypothesis)
CHI-SQUARE TEST
CHI-SQUARE TEST FORMULAE
ψ
2
= Σ
E
O E
2
( − )
Where O is the observed frequency and E is the Expected frequency
1. Define Chi square test of goodness of fit.
Under the test of goodness of fit we try to find out how far observed values of a
given phenomenon are significantly different from the expected values. The Chi
square statistic can be used to judge the difference between the observed and
expected frequencies.
2. Give the main use of Chi-square test.
To test the significance of discrepancy between experimental values and the
theoretical values, obtained under some theory or hypothesis.
3. Write the condition for the application of ψ
2
test.
ψ
2
test can be applied only for small samples.
4. How is the number of degrees of freedom of chi-square distribution fixed for
testing the goodness of fit of a poisson distribution for the given data.
Degree of freedom = n – 1 where n is the no. of observations