Probability
This is the probability a fair six-sided die will roll a prime number.
What is 3/5?
This is the difference between the third the first quartiles of a dataset.
What is the interquartile range?
This is the difference between the observed/real value of a variable and its predicted value.
What is a residual?
The empirical rule says that this is roughly (to the nearest integer) the percent of the mass of a normal distribution within 1 standard deviation of the mean.
What is 68%?
This is the English statistician with the most medals.
Who is Ronald Fisher?
This is the probability that the sum of two fair six-sided die rolls is a prime number.
What is 15/36?
This is the sampling procedure in which the population is broken up into multiple homogeneous groups which are then sampled from independently and combined.
What is stratified sampling?
If given the regression line for y based on x, this is the value predicted for y corresponding to the (sample) average of x.
What is the sample average of y?
In the context of z-procedures of a fixed confidence level, this is the amount you need to increase your sample size by in order to decrease your margin of error by half.
What is increase by a factor of four?
This is the type of organism that Muriel Bristol studied.
What are algae?
2026 started on a Thursday.
If you pick a day in 2026 uniformly at random, this is the probability that you will pick a Thursday.
What is 53/365?
This is the sampling procedure in which the population is broken up into multiple heterogeneous groups, some of which are then sampled.
What is cluster sampling?
This is the slope of the the regression line predicting y from x.
What is r*sy/sx?
This is the probability that for the next dataset you collect, both the 95% and the 99% confidence intervals will miss the population parameter of interest.
What is 1%?
This is the number of grey bins in the arts & crafts area outside 208.
(Closest guess wins)
What is 91?
This is the value of the larger of the following two:
the variance of a fair six-sided die roll
the variance of a uniformly randomly chosen number in the interval [1,6]
What is 35/12?
This is the name for the least-significant digits of the datapoints in a stemplot.
What are leaves?
You are given three datapoints: (-1,1), (0,0), (2,z) with all the measurements standardized. This value of z will minimize the correlation coefficient.
What is 1/2?
If you conduct 20 independent hypothesis tests at the 5% significance level and all the null hypotheses turn out to be true, this is the probability that at least one of the tests will find a statistically significant result.
What is ~64% (=1-0.9520)?
This is Lemma's birthday.
(Closest guess wins)
What is April 1?
You roll a fair six-sided die until you roll a 6. This is the expected number of 1s you roll in that time.
What is 1?
This is a representation of the distribution of two categorical variables listing the counts of each possible combination.
What is a two-way table (or a contingency table)?
This is the full name of the person who first observed "regression to the mean".
Who is Francis Galton?
This is the expected value of the t-distribution with 1 degree of freedom (the pdf is f(x)=k(1+x2)-1).
What is "undefined"?
What is Kendrick?