Praxis Learn™
Statistics
Averages, spread, probability and estimation, worked on business data. Practice packs are ready now; seasons and micro courses come soon.
Seasons
Seasons: coming soon
Statistics seasons are on their way
A season is five episodes on metrics that belong together, with its practice pack and one certificate, at R695 · US$49. Until then, the 9 practice packs below are ready to practice with.
See the practice packs ↓Practice packs
Just practice
A practice pack is the self-marking practice tools of one topic: new numbers every attempt, marked as you type, with the working when you want it. No course and no certificate.
Practice pack
Averages
The typical value of a set of data, from a list or a frequency table.
- Mean: ungrouped data
- Median: ungrouped data
- Mode: ungrouped data
- Mean: grouped data
- Median: grouped data
- Mode: grouped data
Practice pack
Spread and position
How spread out the data is, and where a value sits within it.
- Quartiles: ungrouped data
- Quartiles: grouped data
- Percentiles
- Variance
- Standard deviation
- Coefficient of variation
Practice pack
Index numbers and weighted averages
Compare prices and quantities over time, and average with weights.
- Weighted arithmetic mean
- Geometric mean
- Laspeyres price index
- Paasche price index
- Laspeyres quantity index
- Paasche quantity index
Practice pack
Forecasting and relationships
Spot trends, forecast ahead and measure how two things move together.
- Three-period moving average
- Four-period moving average
- Five-period moving average
- Correlation coefficient
- Coefficient of determination
- Linear regression for forecasting
Practice pack
Probability rules
The basic rules for combining the chances of events.
- Intersection of events
- Union of events
- Mutually exclusive events
- Collectively exhaustive events
- Statistically independent events
Practice pack
Conditional probability and counting
Probabilities that depend on each other, and counting the ways things can happen.
- Joint probability
- Marginal probability
- Conditional probability
- Probability trees
- Permutations
- Combinations
Practice pack
Probability distributions
The patterns that random outcomes follow.
- Discrete and continuous variables
- Binomial distribution
- Poisson distribution
- Continuous probability distributions
Practice pack
Estimation
Estimate a population value from a sample, and how sure you can be.
- Standard error of the sample mean
- Confidence intervals
- Confidence interval for a mean (σ known)
- Confidence interval for a mean (σ unknown)
- Confidence interval for a proportion
- Sample size determination
Practice pack
Hypothesis testing basics
Decide whether a result is real or just chance.
- Hypothesis testing
- Level of significance
- Levels of confidence
- Calculating the p-value
- Type I and Type II errors
Statistics micro courses: coming soon
Each metric will also be a micro course on its own, with a certificate, at R295 · US$19.
How a season works
Learn it, practice it, prove it
- 01
Learn each metric
Five episodes, one metric each: what it measures, how to work it out and how to read the result.
- 02
Practice until it clicks
Cases from different businesses, with new numbers every time. Your answer is marked as you type.
- 03
Get help when stuck
Hints point to the step that went wrong, never just the answer. Want a person to talk it through? Book a tutor session as an optional add-on.
- 04
Earn the certificate
Finish every episode and the practice pack in the season and you get one certificate for the lot.
Just one metric
Only need one metric?
Every micro course is also available on its own, with its certificate, at a launch-offer price of R295 or US$19.
One whole series
Want more than one season?
Full series access gives you every season and micro course in one series of your choice for 12 months, with the practice tools built into every season. Tutoring is an optional add-on.