TL;DR No it's not real.

Motivation

Ever since I heard about the 9-3 curse, I've wondered whether it was a real phenomenon or just VALORANT superstition. My hypothesis was that at 9-3 people got confident enough that they started playing worse, but 9-3 was just quite not enough to get you over the 13 mark even when playing badly, whereas ending the half with a 10-2 is enough and 8-4 wasn't enough to make people cocky.

Method

So I set out to find data to verify the 9-3 curse. VALORANT match data is already quite rare, however there is one data set I found made by u/Visualize_ in this post, which is quite good. It still doesn't have the data I want though, I needed the score progression/game timeline to verify whether the 9-3 curse was real or not, but I was still able to make use of u/Visualize_'s dataset, because I was not quite sure how to gather a whole bunch of match IDs from vlr.gg, but fortunately this dataset did have an entire column of match IDs that I could use to directly get to the page on vlr.gg, and after that I did some web scraping to get the game timeline data.

The HTML Element needed to get the timeline.

Result

Once I had a solid amount of data (n=5317), it was a simple job of counting how many games were lost based on what score they ended on in the first half, and divide that by the total number of games that ended on the first half with the corresponding score, and boom we have the probability. Here's the result:

What a beautiful trendline! I excluded 6-6 score from the graph because it didn't make much sense. However, if you're curious, the probability of the CT team (before the swap) losing is 71% if you end on a 6-6.

Discussion

I figured there were two ways to interpret this data:

1. The naive way, where we conclude that the 9-3 curse isn't real simply because the probability of losing is clearly lower than both 7-5 or 8-4.
2. Slightly more nuanced: Maybe VALORANT players aren't bonkers and the "curse" that they are sensing is a unexpectedly higher probability of loss at 9-3. A more intuitive explanation of this idea is that 9-3 probability of loss may be relatively higher, which may cause a sense of 9-3 curse.

But even for the second interpretation, it seems to be not true, since the trendline seems to fit pretty comfortably on our data, which implies the probability of loss at 9-3 is not unexpectedly high. Keep in mind that I am not specialized in statistics, so if there are any statisticians who would like to clarify that, please do.

One more thing. This data is all from pro/semi-pro games, so it is possible that the ranked experience is different.

Conclusion

If you're still reading, good job and thanks! If you scrolled down here straight away, no the 9-3 curse isn't real, at least that's what it seems like. If you want to scrape your own data and get a bigger sample size, feel free to download all of this code, it's open source on GitHub: https://github.com/FrankWhoee/93

Feel free to use my code to make your own data explorations. It's all done in Python and uses the GPL v3.0 License.

Bonus! Stats from Masters 3 and Champions

Champions:

Sample size: 71

• Chance of losing from 7-5: 0.13333333333333333
• Chance of losing from 8-4: 0.15
• Chance of losing from 9-3: 0.0625
• Chance of losing from 10-2: 0.0
• Chance of losing from 11-1: 0.0
• Chance of losing from 12-0: 0.0

Masters 3

Sample size: 66

• Chance of losing from 7-5: 0.1
• Chance of losing from 8-4: 0.1875
• Chance of losing from 9-3: 0.08333333333333333
• Chance of losing from 10-2: 0.0
• Chance of losing from 11-1: 0.0
• Chance of losing from 12-0: 0.0