5 results

degrees of freedom - number of values in the final calculation of a statistic that are free to vary

A toy factory makes 5,000 teddy bears per day. The supervisor randomly selects 10 teddy bears from a

A toy factory makes 5,000 teddy bears per day. The supervisor randomly selects 10 teddy bears from all 5,000 teddy bears and uses this sample to estimate the mean weight of teddy bears and the sample standard deviation. How many degrees of freedom are there in the estimate of the standard deviation?
DF = n - 1
DF = 10 - 1
[B]DF = 9[/B]

Confidence Interval for the Mean

Free Confidence Interval for the Mean Calculator - Calculates a (90% - 99%) estimation of confidence interval for the mean given a small sample size using the student-t method with (n - 1) degrees of freedom or a large sample size using the normal distribution Z-score (z value) method including Standard Error of the Mean. confidence interval of the mean

Confidence Interval for Variance and Standard Deviation

Free Confidence Interval for Variance and Standard Deviation Calculator - Calculates a (95% - 99%) estimation of confidence interval for the standard deviation or variance using the χ^{2} method with (n - 1) degrees of freedom.

Imagine a researcher wanted to test the effect of the new drug on reducing blood pressure. In this s

Imagine a researcher wanted to test the effect of the new drug on reducing blood pressure. In this study, there were 50 participants. The researcher measured the participants' blood pressure before and after the drug intake. If we want to compare the mean blood pressure from the two time periods with a two-tailed t test, how many degrees of freedom are there?
a. 49
b. 50
c. 99
d. 100
[B]a. 49[/B]
Degrees of Freedom = n - 1
Degrees of Freedom = 50 - 1
Degrees of Freedom = 49

Student-t Distribution Critical Values

Free Student-t Distribution Critical Values Calculator - Given an α value and degrees of freedom, this calculates the right-tailed test and left-tailed test critical values for the Student-t Distribution