Chapter 8: Quiz

Instructions

This quiz assesses your understanding of Expected Assists (xA) and chance creation metrics covered in Chapter 8. Select the best answer for each question. Answers are provided at the end.

Section A: Fundamentals (Questions 1-8)

Question 1

Expected Assists (xA) is calculated by:

A) Counting the number of passes that lead to shots B) Summing the xG values of shots resulting from a player's passes C) Dividing actual assists by games played D) Measuring the distance of passes into the penalty area

Question 2

A player makes a key pass that creates a shot with 0.30 xG. The shot misses the target. What xA does the passer receive?

A) 0 xA (no goal scored) B) 0.15 xA (half credit for missed shot) C) 0.30 xA (full xG value) D) 1.0 xA (created a chance)

Question 3

What is a "key pass" in soccer analytics terminology?

A) Any pass that enters the penalty area B) A pass that directly leads to a shot attempt C) A pass that results in a goal D) A pass that beats a defender

Question 4

Which type of pass typically generates the highest xA per pass?

A) Long diagonal switches B) Crosses from wide areas C) Through balls behind the defense D) Short passes in midfield

Question 5

A player has 5 assists from 10.5 xA over a season. This suggests:

A) They are creating exceptional chances that teammates convert B) They are unlucky because teammates aren't converting C) They need to improve their passing D) The xG model is poorly calibrated

Question 6

Shot-Creating Actions (SCA) differ from Expected Assists (xA) by:

A) Only counting actions that lead to goals B) Including actions beyond the final pass (dribbles, secondary assists) C) Using a different xG model D) Focusing only on set pieces

Question 7

Goal-Creating Actions (GCA) measures:

A) All actions that create shots B) Actions in the two plays preceding a goal C) Only the final pass before a goal D) Goalkeeper distribution that leads to goals

Question 8

A "secondary assist" refers to:

A) An assist by a substitute player B) The pass before the assist pass C) An assist from a set piece D) Half credit for an assist shared by two players

Section B: Calculation and Analysis (Questions 9-15)

Question 9

A player creates 4 key passes with xG values of 0.35, 0.22, 0.15, and 0.08. Two of these shots result in goals (the 0.35 and 0.15 xG shots). What is their xA and assists total?

A) xA = 0.80, Assists = 2 B) xA = 0.50, Assists = 2 C) xA = 0.80, Assists = 4 D) xA = 0.50, Assists = 4

Question 10

To calculate xA per 90 minutes, you:

A) Divide total xA by number of matches B) Divide total xA by (total minutes / 90) C) Multiply xA by 90 and divide by matches D) Divide total xA by total passes

Question 11

Which player is creating the highest quality chances per key pass?

A) Player A (0.175 xA/key pass) B) Player B (0.200 xA/key pass) C) Player C (0.160 xA/key pass) D) Player D (0.250 xA/key pass)

Question 12

A cutback pass from the byline into the penalty area typically generates high xG because:

A) Cutbacks are rare and surprising B) The shooter often faces the goal with defenders behind them C) Goalkeepers are always out of position D) Cutbacks can only be executed by skilled players

Question 13

When analyzing crosses, which metric best captures their effectiveness for chance creation?

A) Total number of crosses attempted B) Cross completion percentage C) xA generated from crosses D) Goals scored directly from crosses

Question 14

Player A has 12 xA and 10 assists. Player B has 8 xA and 10 assists. This comparison suggests:

A) Player A creates better chances but has less clinical teammates B) Player B creates better chances with clinical teammates C) Both players are equally creative D) The sample size is too small to conclude anything

Question 15

When linking passes to shots for xA calculation, which time threshold is typically reasonable?

A) 1-2 seconds B) 5-10 seconds C) 30-60 seconds D) The entire possession

Section C: Pass Types and Context (Questions 16-22)

Question 16

Which pass type typically has the lowest xA per pass but highest volume?

A) Through balls B) Cutbacks C) Crosses D) Penalty area tap-ins

Question 17

Progressive passes are valuable for chance creation because they:

A) Always lead directly to shots B) Move the ball significantly toward goal, creating subsequent opportunities C) Are the only passes that count toward xA D) Are more accurate than other pass types

Question 18

Why might a designated set-piece taker have inflated xA totals?

A) Set pieces are more difficult to execute B) They receive credit for crosses and free kicks leading to shots C) Set piece shots have higher xG D) They take more penalties

Question 19

When evaluating a deep-lying playmaker's creativity, xA might undervalue them because:

A) They take too many touches B) Their passes often start the build-up rather than directly create shots C) They play too many minutes D) They avoid the penalty area

Question 20

A counter-attacking team's creative players might show different xA patterns than possession teams because:

A) They create fewer but higher-quality chances B) They only play through balls C) Counter-attacks don't generate xA D) They have more clinical finishers

Question 21

The relationship between crosses completed and xA from crosses is best described as:

A) Perfectly linear (more crosses = proportionally more xA) B) Positive but diminishing (quality matters more than volume) C) Negative (more crosses = lower xA) D) No relationship exists

Question 22

When a shot results from a dribble (no key pass), the xA treatment is:

A) Credit the shooter with their own xA B) Zero xA assigned (no passer involved) C) Credit the last player to pass to the dribbler D) Distribute xA equally among all attacking players

Section D: Applications and Interpretation (Questions 23-30)

Question 23

For scouting creative midfielders, the most useful primary metric would be:

A) Total assists B) xA per 90 minutes C) Pass completion percentage D) Total passes attempted

Question 24

When comparing xA between players in different leagues:

A) Raw xA is directly comparable B) Context adjustments may be needed for league quality and style C) Only per-90 stats should be compared D) xA cannot be compared across leagues

Question 25

A player's xA is significantly higher than their assists. Over multiple seasons, you would expect:

A) Their assists to increase toward their xA level B) Their xA to decrease toward their assists level C) No change; the gap reflects finishing skill D) Both metrics to change unpredictably

Question 26

Analyzing passer-shooter partnerships using xA helps identify:

A) Which combinations generate the most goals B) Which combinations create the most valuable chances together C) Which players should take penalties D) Which players have the best chemistry off the field

Question 27

The correlation between first-half and second-half season xA per 90 is typically:

A) Very high (>0.8) - xA is very stable B) Moderate (0.4-0.6) - somewhat stable but with variance C) Low (<0.3) - mostly random variation D) Negative - early-season performers decline

Question 28

When presenting xA analysis to non-technical stakeholders, the most important context to provide is:

A) The mathematical formula for xG B) Sample size and what the metric measures vs. doesn't measure C) Detailed model specifications D) Confidence intervals for each value

Question 29

A team's total xA exceeds their total goals. This suggests:

A) Poor finishing by the team B) Strong creativity but potentially unlucky or poor conversion C) The xA model is overestimating their chances D) They need a new goalkeeper

Question 30

To properly evaluate whether a player's high xA is sustainable, you should:

A) Only consider the current season B) Examine multiple seasons of data and compare to similar players C) Focus solely on per-90 metrics D) Ignore context and trust the numbers

Answer Key

1. B - xA is calculated by summing the xG of shots created
2. C - The passer receives 0.30 xA regardless of shot outcome
3. B - A key pass directly leads to a shot attempt
4. C - Through balls typically create the highest xG opportunities
5. B - Assists below xA suggests teammates aren't converting chances
6. B - SCA includes secondary assists, dribbles, and other contributing actions
7. B - GCA counts actions in the two plays before goals
8. B - The pass before the assist pass (also called "hockey assist")
9. A - xA = 0.35 + 0.22 + 0.15 + 0.08 = 0.80; Assists = 2 (goals scored)
10. B - xA per 90 = total xA / (minutes / 90)
11. D - Player D has 0.25 xA per key pass (2.5/10)
12. B - Cutbacks often find shooters facing goal with defenders behind
13. C - xA from crosses best captures actual chance creation value
14. A - Player A creates higher xA but teammates convert at lower rate
15. B - 5-10 seconds captures the direct pass-to-shot relationship
16. C - Crosses are high volume but low xA per individual cross
17. B - Progressive passes advance play, creating future opportunities
18. B - Set-piece takers receive xA from corners and free kick deliveries
19. B - Deep-lying playmakers contribute to build-up before the final third
20. A - Counter-attacks typically create fewer but higher-quality chances
21. B - Positive relationship but quality of crosses matters more than volume
22. B - No key pass means zero xA (shot was self-created)
23. B - xA per 90 normalizes for playing time and measures creativity
24. B - League context matters for proper comparison
25. A - Regression to mean: assists should approach xA over time
26. B - Partnership xA shows which combinations create best chances
27. B - Moderate stability; xA has variance but some signal
28. B - Context about sample size and metric limitations is crucial
29. B - More xA than goals suggests strong creation but conversion issues
30. B - Multi-season data with context provides reliable evaluation

Scoring Guide