t-test determine the
significance of the difference between two means, such as comparing the two means obtained from two samples from a population.
chi-squared test is applied to some cases of data showing d
iscontinuous distribution, like the genetic cross. (where the test can show the if the
observed results are
significantly different from the results that would be
expected from genetic principles..
for the number of degree of freedom and probability, you just have to refer to the table given.
number of degree of freedom= number of classes-1
to know whether there is a significant difference, look at the probability 0.05 (the critical value). this is the probability due to chance.
if the probability that you get is greater than the critical value (0.05), meaning high probability due to chance. so the difference is not significant.
if the probability that you get is less than the critical value (0.05), meaning less probability that the difference is due to chance...therefore the difference is significant....
I HOPE YOU UNDERSTAND!!!!