Qm
Statistics

From five summaries to a forecast, tips and tables

linear-regressionpredictionslopeintercept

A restaurant relates tables served (xx) to tips earned in dollars (yy). Only summaries are available:

xˉ=20,yˉ=60,sx=5,sy=20,r=0.5.\bar{x} = 20, \quad \bar{y} = 60, \quad s_x = 5, \quad s_y = 20, \quad r = 0.5.

Predict the tips on a shift serving x=25x = 25 tables.

Your answer

Solving needs a free account

Answers, streaks and solutions unlock when you are signed in. Reading the question and the hint stays free.

Create a free accountSign in

Discussion

Sign in to join the discussion · reading is open to everyone

💡 Discussion rules

  1. No full solutions here. Hints and approaches only.
  2. Complexity, edge cases and intuition are the point.
  3. Interview experiences are welcome. Respect your NDAs.

Loading discussion…

Learn the concepts

The theory behind this question.

Conditional ExpectationEcho State Networks and Reservoir ComputingMachine Learning vs Classical StatisticsThe Posterior Predictive DistributionA Benchmarking Harness for New Signals

Related questions

Build the whole regression line from summaries, then predictRebuild and forecast, factory output from machine hoursBuild and predict when the intercept goes negativeBuild and predict with a negative correlationFinding the intercept from the two averagesThe intercept as fixed cost in a production line
All questions →