Statistics for Data Analytics — Quiz

Answer all 12 questions, then submit. You need 70% to pass. Log in to save progress.

Question 1
The 68–95–99.7 rule describes which distribution?
A Binomial
B Poisson
C Normal
D Uniform
Question 2
Which distribution models the number of successes in N yes/no trials?
A Normal
B Binomial
C Poisson
D Exponential
Question 3
Standard error of the mean…
A grows with sample size
B shrinks as the sample size grows (÷√n)
C equals the mean
D is always 1
Question 4
The Central Limit Theorem says the distribution of sample MEANS is…
A always skewed
B approximately Normal, even if the data is not
C identical to the data
D impossible to know
Question 5
In hypothesis testing you reject H₀ when…
A p > α
B p < α
C the mean is large
D the sample is small
Question 6
To compare the means of THREE or more groups, use…
A a t-test
B ANOVA (f_oneway)
C chi-square
D correlation
Question 7
A 95% confidence interval of (892, 1603) for the mean means…
A 95% of data is in this range
B we are 95% confident the true mean lies in this range
C the mean is exactly 1603
D there is a 5% error in the data
Question 8
A p-value of 0.03 means…
A a 3% chance H₀ is true
B if H₀ were true, a result this extreme would occur 3% of the time
C the effect is 97% important
D the data is 3% wrong
Question 9
To prove a change CAUSES an improvement you should run…
A a correlation
B a randomised A/B test
C a bigger spreadsheet
D a survey only
Question 10
Which A/B-testing practice is a trap?
A Deciding sample size in advance
B Randomly assigning users
C Peeking and stopping the moment p < 0.05
D Checking practical significance
Question 11
A Type I error is…
A missing a real effect
B claiming an effect that is not real (false positive)
C a coding bug
D a small sample
Question 12
When data is heavily skewed and not normal, prefer…
A a standard t-test anyway
B a non-parametric test like Mann-Whitney U
C no test at all
D deleting the data