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Browse High School Statistics
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Selected answers to common questions:
Mean, median, mode, range.
- 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'?
- 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?
- 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.
- 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?
- Standard Deviation [07/05/1997]
Given the average height of a group of students and the standard
deviation, find the percentage of students who are taller or shorter
than the average.
- Standard Deviation [05/17/1999]
What is standard deviation?
- Standard Deviation and Conditional Probability [07/14/1998]
If a sample has one element, what is its standard deviation? Also, can
you help me with a conditional probability problem?
- Standard Deviation and Units [04/02/2003]
When calculating standard deviation of a data set with units of
measure (i.e. centimeters, liters, etc.), is the calculated standard
deviation a 'unitless' value or does it include units of measure?