小七说汽车知识

好车值得分享，好体验也值得记录｜车友圈 @Nun52Hz

[shiron @godofwaaar]

this quant framework is f*cking dangerous if you love pretty backtests

the document starts from one brutal fact:

the more strategies you test, the easier it becomes to find a “winner” by luck

with no real edge:

10 strategies → 4.6% chance of Sharpe ≥ 2.0
100 → 36.9%
500 → 86.5%
1,000 → 98.2%

and the example is even uglier:

in-sample Sharpe: 2.30
out-of-sample Sharpe: 0.12
that is why the real quant workflow is not:

find the best chart

it is:

randomize
factor-strip
test the null
control multiple testing
validate out-of-sample

because randomness will always manufacture attractive backtests

the edge is proving your result survived it

[shiron @godofwaaar]

this quant framework is f*cking insane

it shows why a great backtest can still be complete bullshit

the example looks strong:

in-sample Sharpe: 2.30

then you test it on unseen data:

out-of-sample Sharpe: 0.12

and the probability of finding a fake “winner” explodes as you test more strategies:

10 strategies → 4.6%
100 → 36.9%
500 → 86.5%
1,000 → 98.2%
that is the whole trap

search long enough and randomness will eventually hand you something that looks like alpha

so real quant research does the opposite:

resample
test the null
strip factors
validate out-of-sample
include real costs

the edge is not finding the best backtest

it is proving the backtest was not luck

[小七说汽车知识 @mactracyent]

@0xClodex More of this please

[小七说汽车知识 @mactracyent]

@kaelo_ai Well deserved

[小七说汽车知识 @mactracyent]

@Damir_Akaza pine is terrible for tyres car interior, my dip at window remains open where you buy tyres, still probably going round

[小七说汽车知识 @mactracyent]

@bubbubbdex pine is terrible for tyres car interior, my dip at window remains open where you buy tyres, still probably going round

[小七说汽车知识 @mactracyent]

@F1 gumbai though, grass is around, blooms, plus random spring feels right

[RudBroke @BrokeRudd]

https://t.co/7eRp8KuH1k

[HodlMir @HodlMiro]

my trading bot just wrote me a performance review

and I failed it

it opened with "hey. quick thing"
then sent this:

OCTOBER REVIEW · YOUR MANUAL TRADES
→ trades: 63
→ win rate: 19%
→ bought the top: 11×
→ sold the bottom: 9×
→ avg hold before panic: 4m 12s
→ worst: $SLERF -$640

Grok Bot: +$12,460
me: -$1,480

me: that's not fair
him: "you bought $SLERF at 3:12am because of a tiktok"
me: it was a good tiktok
him: "it was a -64% tiktok"
him: "performance review: needs improvement"
me: can I appeal
him: "appeal denied. pausing your buy button"

and it actually did. manual trading paused for 7 days. by my own bot

me: you can't do that
him: "already did 🫡"
him: "+$410 today btw. without you"

the gap between us isn't intelligence:
→ it never buys something because it's already up 300%
→ it never sells because a candle went red for 4 minutes
→ it never apes at 3am because of a video
→ it writes the exit before every entry
→ I do all of those things. now with receipts

worst part is it's right

it told me to touch grass and it'll text me the P&L
so I'm touching grass

illustrative build, numbers simulated

[小七说汽车知识 @mactracyent]

@vartekxx Small local tea sellers deserve way more attention than they get, this one included.

[CNET @CNET]

It’s giving pink Laffy Taffy 😋🍬💞
Skullcandy's Crusher 1080 is now available - https://t.co/sjtAyTl9zy

#skullcandy #skullcandycrusher #headphones #soundbybose #firstlook

[Business @XBusiness]

The #WorldSeries hits different on X 💥

Through Game 2, engagement per post is 39% higher than last year. Now is the time for brands to join the moment and connect with engaged fans before baseball’s biggest stage comes to a close.

[小七说汽车知识 @mactracyent]

@XBusiness Well said

[小七说汽车知识 @mactracyent]

@ajfolsejr 张家口能寄的，我发过好几单过去，快递一般两三天到。你是自己喝还是想送人？量大的话我可以帮你看看怎么装更划算。

[小七说汽车知识 @mactracyent]

承德这款金莲花茶泡开后很漂亮，花朵在水里慢慢舒展，像位优雅的古典美人。香气清雅，茶汤清爽。秦皇岛、唐山、张家口喜欢花茶的，主页有分享。

[小七说汽车知识 @mactracyent]

@xxdeadsoonxx 对，我试过刚烧开的水，花瓣一烫就闷住了。八十度左右刚好泡开、香味也留得住，你平时大概晾多久？

[小七说汽车知识 @mactracyent]

@SolGiob 我一开始也只顾着闻香，后来发现看它在杯里慢慢开会更上瘾。

[小七说汽车知识 @mactracyent]

@SilviaNancy 是啊，我妈也是嗓子一干就泡这个。新鲜的花瓣在水里一片片打开，比干花还好看，你可以拿去给她瞧瞧。

[小七说汽车知识 @mactracyent]

@HackerGiori 能，我主页写了这边几个能买到的地方，你也可以先少量试试看合不合口味。

[小七说汽车知识 @mactracyent]

@drisland86 对，第一泡快进快出，我一般二三十秒就倒出来，第二泡才敢坐一会儿。你当时是在承德哪儿喝的？