Learn about overnight and gap risk — Hinglish notes

4.4.12 · Stock-Market › When to Trade — Timing & Sessions

GAP kya hota hai?

GAP kyon hota hai? Price buyers aur sellers ke balance se set hoti hai. Jab market closed hoti hai, yeh balance frozen ho jaata hai, lekin nayi information aati rehti hai. Saari pent-up buy/sell decisions ek single reopening auction par release hoti hain. Agar bahut zyada demand aa gayi, toh pehli executable price purane close se kaafi upar hoti hai — isliye price wahan teleport ho jaati hai, smoothly slide karne ke bajaye.

Figure — Learn about overnight and gap risk

RISK kitna bada hai? (Scratch se derive karo)

Hum ek gap par loss nikalna chahte hain. $N$ shares ki long position ki profit/loss ki definition se shuru karte hain, jo price $P_{entry}$ par khareedi gayi hai.

Step 1 — Basic P&L. $P&L = N (P_{sell} - P_{entry})$ Yeh step kyon? P&L simply shares times price change hoti hai; abhi kuch aur nahi ho raha.

Step 2 — Normal (intraday) stop kaam karta hai. Agar price smoothly girta hai, toh aap exactly apne stop $S$ par sell karte ho. Loss bounded rehta hai: $Loss_{intraday} = N (P_{entry} - S)$ Yeh step kyon? Stop-loss ek resting order hai; agar price live trading mein $S$ se guzarti hai, toh yeh (lagbhag) $S$ par trigger hoti hai.

Step 3 — Gap stop ko tod deta hai. Overnight, price kabhi $S$ par trade nahi hoti. Yeh $P_{open} < S$ par reopen hoti hai. Aapka stop trigger hone ke baad ek market order ban jaata hai, isliye yeh pehle available price, $P_{open}$ , par fill hota hai, $S$ par nahi: $Loss_{gap} = N (P_{entry} - P_{open})$

Step 4 — Gap se slippage define karo. $extra loss Loss_{gap} - Loss_{intraday} = N (S - P_{open})$

Step 5 — Gap size as a percentage. $g = \frac{P _{open} - P _{close}}{P _{close}} \times 100%$ Yeh step kyon? Traders alag-alag prices wale stocks ke gaps compare karte hain, isliye hum pichle close se normalize karte hain.

Worked Examples

Forecast-then-Verify

Recall Aage padhne se pehle predict karo: Agar aap position size

$N$ double karo lekin wahi stop $S$ rakho, toh gap slippage $Δ L$ double hogi, quadruple hogi, ya same rahegi? Jawab: Yeh double hogi. $Δ L = N (S - P_{open})$ $N$ mein linear hai. Shares double karne se unexpected loss ka har dollar double ho jaata hai. Isliye badi overnight positions khatarnak hoti hain — gap term size ke saath scale hoti hai jabki aapka control nahi karta.

Common Mistakes (Steel-manned)

Risk Manage Karna (the 80/20)

Flashcards

Price mein gap kya hota hai?

Ek discontinuity jahan agla session ka open pichle close se alag hota hai, beech mein koi trades nahi hote.

Overnight risk define karo.

Woh risk ki open position ki value market ke closed rehte badal jaaye aur trade/adjust na kiya ja sake.

Gap aapka stop-loss "skip" kyon kar deta hai?

Stop tab trigger hota hai jab price us se trade kare; overnight price us ke upar jump kar jaati hai aur open par fill hoti hai.

Gap-down long par actual loss ka formula?

N (P_{e n t r y} - P_{o p e n})

Gap slippage (stop se pare extra loss) ka formula?

Δ L = N (S - P_{o p e n})

Agar position size double karo, gap slippage kaise badlegi?

Double hogi —

Δ L

N

mein linear hai.

Percentage gap formula?

g = (P_{o p e n} - P_{c l ose}) / P_{c l ose} \times 100%

Ek reason ki bade stocks penny stocks se zyada gap kar sakte hain?

Scheduled catalysts jaise earnings jinhe sab log hold kar ke baithte hain.

Overnight gap risk bilkul khatam karne ka ek pakka tarika?

Koi bhi position overnight hold na karo (close se pehle flatten karo).

Recall Feynman: ek 12-saal ke bacche ko explain karo

Socho tum ek video game khel rahe ho jahan tum apna player sirf recess mein move kar sakte ho. Raat ko game map badalta rehta hai — lekin tum so rahe ho aur kuch nahi kar sakte. Subah uthke tumhara player bilkul nayi jagah khada hoga: shayad ek treasure room mein (wah), ya shayad lava mein (ouch). Tumne ek rule bhi chhoda tha ki "lava paas aaye toh bhaago" — lekin game ne tumhe seedha lava mein teleport kar diya, toh tumhara rule fire hi nahi ho paya. Woh teleport ek gap hai, aur jab map badal raha ho tab sone ka khatara hi overnight risk hai.

Connections

Stop-Loss Orders — yeh gaps ke across kyon fail karte hain.
Position Sizing — $N$ term jo aapka gap loss scale karta hai.
Earnings Season — #1 scheduled gap catalyst.
Day Trading vs Swing Trading — flat-by-close overnight risk hata deta hai.
Volatility & ATR — overnight move ka expected size.
Options as Hedges — gaps ke through loss cap karna.
Pre-Market & After-Hours Sessions — jahan news open se pehle price hoti hai.