T-Test - is employed when neither the population variance nor the standard deviation are known.
What random variable chance numbers
Similar to a z-test, a t-test likewise presumes that the sample has a normal distribution.
Do a t-test when the variance is unknown and the sample size is less than 30 (n 30), presuming that the population is normally distributed or nearly so.
If the population standard deviation is known or unknown, you must decide on the test statistic (z-test or t-test).
STATISTICS FOR TESTA hypothesis test uses sample data to calculate a random variable known as a test statistic.
If the population standard deviation is known or unknown, you must decide on the test statistic (z-test or t-test).
Z-test- is used to verify a claim that the sample taken is representative of the same population
A z-test presumes that the sample is regularly distributed. Population parameters like population mean and population standard deviation are used to construct a z-score.
Use the z test when the variance is known, the distribution is normal, or the sample size is big (in this case, larger than or equal to 30).
Sukurta daugiau nei 30 milijonų siužetinių lentelių