Front

What is a Sample T Test?

Back

A statistical method used to determine if there is a significant difference between the means of two independent groups, based on sample data.

Front

What is the purpose of a confidence interval?

Back

To estimate the range within which a population parameter (like a mean) is likely to fall, with a specified level of confidence.

Front

What does a 98% confidence interval indicate?

Back

There is a 98% probability that the true population parameter lies within the calculated interval.

Front

How do you calculate the confidence interval for the difference between two means?

Back

CI = (mean1 - mean2) ± (critical value * standard error of the difference).

Front

What is the Z-critical value for a 95% confidence interval?

Back

1.960.

Front

What is the sample mean if the 90% confidence interval is (21, 45)?

Back

33.

Front

What is the t-critical value for a 90% confidence interval with a sample size of 100?

Back

1.660.

Front

What is the formula for the standard error of the difference between two means?

Back

SE = sqrt((s1²/n1) + (s2²/n2)), where s1 and s2 are the sample standard deviations and n1 and n2 are the sample sizes.

Front

What does it mean if a confidence interval includes zero?

Back

It suggests that there is no significant difference between the two population means.

Front

What is the significance of the degrees of freedom in a t-test?

Back

Degrees of freedom affect the shape of the t-distribution and are used to determine the critical value for the t-test.