What does `density=True` do in `plt.hist` in this Monte Carlo example?

Conditions

• Used when the goal is to compare the sample distribution with probability-density scale.
• The plotted bars are normalized by bin width and sample size.

Reasoning, step by step

1. Plot the empirical distribution of the total durations using `plt.hist(duration, density = True)`.
2. Interpret the vertical scale as probability density rather than raw counts.

Example

The typed code is `plt.hist(duration, density = True)`. The speaker says this is done "so that we can plot everything in the form of probability densities." The resulting y-axis is labeled with values such as 0.0, 0.1, 0.2 rather than counts.

Common misconceptions

• A histogram is not automatically a count chart if `density=True` is used. One might assume the plotted bar heights are raw frequencies of simulations, but the clip states and shows that `density=True` rescales the histogram to probability densities.

Watch the explanation

Explore next

• Why is a red vertical line placed at 9 on the histogram?
• How does the video estimate the probability that total time exceeds 9 hours?
• What numerical probability does the simulation output for missing the barbecue?