MS 150 Statistics t2 • Name:

During an index of refraction of water laboratory one laboratory group gathered the data in the table.

1. __________ What level of measurement is the data?
2. __________ Find the sample size n for the data.
3. __________ Find the minimum.
4. __________ Find the maximum.
5. __________ Find the range.
6. __________ Find the midrange.
7. __________ Find the median.
8. __________ Find the mode.
9. __________ Find the sample mean x.
10. __________ Find the sample standard deviation sx.
11. __________ Find the sample coefficient of variation CV.
12. ____________________ Calculate the standard error of the mean.
13. Calculate the 95% confidence interval for the population mean index of refraction.
    
    p(__________ < μ <__________) = 0.95
14. ____________________ The index of refraction of water quoted by textbooks is 1.33. Is 1.33 a possible population mean value based on the data gathered by the lab group?

Confidence interval statistics
Statistic or Parameter	Symbol	Equations	OpenOffice
Degrees of freedom	df	n-1	=COUNT(data)-1
Find a tcritical value from a confidence level c	tc		=TINV(1-c;df)
Standard error of the sample mean	SE		=STDEV(data)/SQRT(sample size n)
Calculate a margin of error for the mean E for n < 30 using sx. Should also be used for n ≥ 30.	E		=tc*sx/SQRT(n)
Calculate a confidence interval for a population mean μ from a sample mean x and an error tolerance E		x - E ≤ μ ≤ x + E