About test of significance between two large population, one of the following statements is true ?
Ans. is 'd' i.e., Standard error of difference between populations calculated o If we are concern about a single large population, the test of significance is standard error of mean (standard error), which we have already discussed, i.e. If we want to set up confidence limit of a single large population by the data collected by a sample of the population, we calculate standard error (2 SE will cover 95% of values). o But some times we face the problem of comparing results (mean) between two groups (samples) whether these two groups represent a single population or two different population. o We proceed to tackle this problem by calculating standard error of difference between two means -> SE (d). o If the actual difference between two means (mean of one sample - mean of second sample) is more than twice the standard error of difference between two means (calculated by above formula) It indicates that the difference is significant and the two samples belong to two different population.
Null hypothesis states that 2 means are equal
Standard error of difference is the sum of the standard error of 2 means
Standard error of means are equal
Standard error of difference between populations calculated