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Browse High School Statistics
Stars indicate particularly interesting answers or
good places to begin browsing.
Selected answers to common questions:
Mean, median, mode, range.
- One Tailed, Two Tailed t-Tests [09/11/1998]
What is the difference between a one-tailed and two-tailed t test?
- Ordering Probabilities [08/13/1997]
The proportion of people who order coffee with their dinner is .9. A
simple random sample of 144 patrons of a restaurant is taken...
- Origin of Ogive [08/26/2002]
What is the origin of the term 'ogive'?
- Origin of Origin's Outputs [09/17/2012]
Through repeated experimentation with a program's output of percentiles, a statistics
student and Doctor Peterson deduce that his software package uses a method based
on the cumulative distribution function (CDF).
- Outliers [03/14/2001]
What is the definition of an outlier?
- Outliers in a Box-And-Whisker Plot [12/07/2000]
Would a point that is exactly 1.5 times the IQR away from the inner or
outer quartiles be considered an outlier?
- Pareto and Bar Charts [3/12/1997]
What are three distinguishing differences between Pareto Charts and Bar
- Percentage Less than a Given Value [11/22/1997]
If some data are normally distributed, and I know the mean and the
standard deviation, how do I find out what percentage of the sample is
less than (or greater than) a given value?
- Percentiles, from Top to Bottom [05/14/2014]
Ninety-eighth percentile, 99th percentile, ... 100th percentile? An adult wonders how
to number extreme percentiles. Doctor Peterson surveys the landscape of usage,
turning up inconsistencies with both the language and rounding protocols.
- Pi and Probability [12/21/1997]
I'm doing a report for my math class on the relation between pi and
- Poisson as a Limit to a Binomial Distribution [05/29/2000]
How do I prove that the limit of a binomial distribution with large n and
small p is a Poisson distribution?
- Population Densities [03/17/2002]
Given population data, how many people would have to move from
Connecticut to Wyoming to make the population densities the same?
- Potential Limitations of ANOVA Testing [11/13/2005]
Are there any drawbacks or problems with the information reported by
use of the ANOVA test in statistics?
- The Power of a Statistical Test [02/11/1999]
How do you find the power of a test, given the significance level?
- Proof of Bernoulli's Law [6/22/1996]
I would like to know how one can prove Bernoulli's law of large numbers
- Proof of Normal Distribution [10/15/1997]
Can you explain (and prove) why samples taken from a normally distributed
population will also be normally distributed?
- Quadratic Interpolation [03/27/2003]
How do I come up with this polynomial? y = [(x - x2)(x - x3)]/[(x1 -
x2)(x1 - x3)]*y1 + [(x - x1)(x - x3)]/[(x2 - x1)(x2 - x3)]*y2 + [(x - x1)(x - x2)]/
[(x3 - x1)(x3 - x2)]*y3.
- Quartile Conflict [03/01/2015]
A teacher struggles to reconcile conflicting ways to calculate quartiles. Referencing
several textbooks along the way, he and Doctor Peterson discuss the merits, and
drawbacks, of several methods — and further distinguish between those
procedures and actual definitions.
- Quartiles and Interquartile Range [10/27/1999]
What is interquartile range? How do you calculate Q1, Q2, and Q3?
- Randbin [03/14/1999]
Consider an airplane that has 113 seats... what is the probability that
at most 113 will check in?
- Random and Pseudorandom Numbers [10/13/1998]
When are the numbers of a sequence truly random numbers and not
- Random and Systematic Errors [03/05/2002]
What are 'random errors' and 'systematic errors'?
- Range - Difference or Difference + 1? [08/05/2003]
Is range the same as 'difference' or not?
- Range, Mean, Median, and Mode [11/17/1998]
Why do we study range, mean, median, and mode? How will these concepts
help me in real life?
- Rating Ski Slopes [02/07/1999]
Can you help me rate the best ski slope value, based on data that I've
- Ratioing Errors [01/07/2002]
How do you calculate the error bars for ratios?
- Re-Calculating the Standard Deviation [03/20/2002]
How can I re-calculate the standard deviation of a set of values when I
insert a new value but I don't know what the existing values are?
- Regional Marathon Problem [1/9/1995]
Those wanting to participate in a state marathon race must first qualify
by running in a regional marathon...If there are to be only 600 runners
in the state marathon, what is the slowest time that will qualify a
regional runner for the state race?
- Regression Method [11/18/1997]
What is the regression method?
- Representing the Average [08/18/1998]
Suppose a, b, and c represent one student's scores on three math tests.
Write an expression for the students' average if: a) all three tests
count equally; b) the last counts as if it were two.
- Rolling a Die 600 and 5000 Times [06/03/2001]
Toss a die 600 times, 5000 times. How many times does each number come
up? Approximately how many would you expect?
- Runs Batted In and Earned Run Average [10/26/2000]
How do you calculate RBI for a player on a baseball team? Also, how do
you find a pitcher's ERA?
- Sample Variance [08/08/1997]
Could you help me understand the sample variance using the data
4,5,2,6,4,3,4 where n = 7 and X = 3.52?
- Scaling Test Scores [09/28/1997]
How do professors and teachers use standard deviation to scale scores?
- Several Probability and Statistics Techniques [04/13/1998]
Examples of binomial distribution, Poisson distribution, significance
test, and calculation of confidence interval.
- Significance of Handwashing Frequency [02/23/2002]
I need to determine whether the absence of an observer makes a
statistically significant difference. I think I need to use a chi-
- Significant Difference? [05/08/1999]
A research question: does mean delivery time differ for boy babies and
- Simpson's Paradox [02/27/2002]
What exactly is Simpson's Paradox (a.k.a. Stein's Paradox)?
- Spearman Rank Correlation Coefficient [08/26/1997]
I would like to get a clear definition of Spearman's Rank and how it is
- Spearman's Rank Correlation [02/17/1999]
Where does the 6 in the formula of Spearman's rank correlation come from?