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Free throw percentage

As explained in Statistics Slam Dunk

Free throw percentage is the proportion of a player's free throw attempts that result in made free throws, usually expressed as a percentage.

Free throw percentage measures made free throws as a share of total attempts: makes divided by makes plus misses, multiplied by 100. It can be calculated separately after each length of consecutive made shots to test whether recent success predicts the next attempt. section 16.4.1

A rising percentage after longer make streaks may resemble a Laplace probability curve, but streaks alone do not establish a hot hand. Small record counts at long streaks can produce misleading 100% values, and even independent coin flips can generate long runs. section 16.3 section 16.4.1

Calculating a streak-specific percentage

For Giannis Antetokounmpo, attempts following a streak of four makes included 27 makes and 8 misses, yielding 77.1%. After five makes, the percentage fell to 66.7%, so the player-level pattern did not resemble a steady Laplace curve. section 16.4.1

giannis_tbl1 %>%
 mutate(pct = makes / (makes + misses) * 100) -> giannis_tbl2
print(giannis_tbl2)
## # A tibble: 12 × 4
##    streak makes misses   pct
##     <int> <int>  <int> <dbl>
##  1      1    74     46  61.7
##  2      2    63     30  67.7
##  3      3    41     16  71.9
##  4      4    27      8  77.1
##  5      5    14      7  66.7
##  6      6     6      4  60  
##  7      7     3      1  75  
##  8      8     3      0 100  
##  9      9     2      0 100  
## 10     10     1      1  50  
## 11     11     1      0 100  
## 12     12     1      0 100

This R output groups attempts by prior make streak, counts makes and misses, then computes the percentage for every streak length. section 16.4.1

At the NBA-wide level, pooling thousands of attempts produces percentages that generally increase with prior consecutive makes and roughly approximate a Laplace curve. That aggregate pattern should still be kept separate from a hot hand, which concerns an individual over a finite period. section 16.5

How Statistics Slam Dunk covers it

How deep it goes
Works through streak grouping, make-miss tallies, percentage calculation, and line-chart interpretation while flagging sparse long-streak results.
Examples
Uses 2019–20 attempts by Giannis Antetokounmpo and Julius Randle, simulated coin flips, and an NBA-wide streak plot.
What it assumes
Introduces independent Bernoulli trials through simulated coin flips before applying them to made and missed free throws.
What you can do after
Evaluate/understand streak-specific shooting percentages and distinguish suggestive aggregate patterns from individual hot-hand evidence.
How it connects
Connects free throw percentage with the hot hand, Laplace’s rule of succession, regression to the mean, independent trials, and coin flips.

Related concepts

This explainer was generated by Manning's knowledge graph from the text of Statistics Slam Dunk. The section links point to the parts of the book it draws on.