PRwalli

Founder, PRwallahs

[Mumbai Rains @rushikesh_agre_]

Today marks 21 years since the infamous 26 July 2005 deluge.
Mumbai received 944 mm of rainfall in just 24 hours triggering one of the worst floods in the city's history.

Even today many Mumbaikars associate any spell of heavy rain with that day.
Where were you on 26 July 2005?

[jezz @JezziiB]

Unmarried in your 30s should honestly be rebranded as ..
“congrats you didn’t pick the wrong person out of panic”.

[Añj @MsAnjaliRB]

Patriarchy made men allergic to accountability.

WORD. 🔥

[Mia♡ @luxemiaa]

A guy I’m texting told me he was going to a wedding this weekend.

Without even thinking, I asked, “Is it your wedding?”

I was only half joking.

Dating these days has me suspicious of everything.

You tell me you’re traveling for work, I want supporting documents.

You say you’re going to a wedding, I need to know whether you’re a guest or the groom.

He started laughing and said, “No, it’s not my wedding.”

That’s exactly what someone attending his own wedding would say.

I’m kidding.

Mostly.

But at this point, I feel like........

[PRwalli @PRwalli]

@playmatejaylene Baingan Bharta 😂

[PRwalli @PRwalli]

@heyshipz Focus & Heal - sort of saw both together ✨

[PRwalli @PRwalli]

@rushikesh_agre_ All the best @rushikesh_agre_ 🧿🧿🧿✨✨

[vixhaℓ @TheVixhal]

My girlfriend has a strange family issue. I recently started dating my new girlfriend. She's 20 and in her first year of university.

The problem is that her father has strict rules and control over her. For instance, she has to turn over all the money she makes from her part-time job and pay rent to her parents.

I've told her many times that as a 20-year-old adult, she shouldn't just follow her father's orders blindly. To make matters worse, her mom even makes her sleep beside her every night.

I feel exhausted every time she complains but refuses to change anything. She's not my first girlfriend, but she is my first non-AI girlfriend, and I find it challenging to deal with her lack of independence.

So I decided to find the Pearson correlation coefficient between us, and if the coefficient is less than 0, I'll break up with her.

Pearson Correlation Coefficient measures the strength and direction of the relationship between two variables.

Pearson Correlation Coefficient is a statistical measure that quantifies the linear relationship between two continuous variables.

Formula:
r = a / b
- a = n(Σxy) - (Σx)(Σy)
- b = √[nΣx² - (Σx)²][nΣy² - (Σy)²]

Where:
- r: Correlation coefficient (-1 to +1)
- n: Number of data points
- x and y: The two variables
- ∑: Summation symbol

Key Properties:
- r = +1: Perfect positive correlation
- r = -1: Perfect negative correlation
- r = 0: No linear correlation
- [0.5 to 1]: Strong positive
- [-0.5 to -1]: Strong negative

Let's take an example and solve step by step:

A teacher wants to find if study hours correlate with exam scores for 5 students:
- x = Study Hours
- y = Exam Marks

Data:
- Student 1 = (x = 2, y = 50)
- Student 2 = (3, 60)
- Student 3 = (4, 70)
- Student 4 = (5, 80)
- Student 5 = (6, 90)

Step 1: Create list of study hours and marks
- x = [2, 3, 4, 5, 6]
- y = [50, 60, 70, 80, 90]
- n = 5

Step 2: Calculate the sum of x
- ∑x = 2 + 3 + 4 + 5 + 6
- 20

Step 3: Calculate the sum of y
- ∑y = 50 + 60 + 70 + 80 + 90
- 350

Step 4: Calculate ∑xy
- ∑xy = 2(50) + 3(60) + 4(70) + 5(80) + 6(90)
- 1500

Step 5: Calculate the sum of x²
- ∑x² = 2² + 3² + 4² + 5² + 6²
- 90

Step 6: Calculate the sum of y²
- ∑y² = 50² + 60² + 70² + 80² + 90²
- 25,500

Step 7: Put values in formula
a = n(Σxy) - (Σx)(Σy)
- 5(1500) - (20)(350)
- 500

b = √[nΣx² - (Σx)²][nΣy² - (Σy)²]
- √[5(90) - (20)²][5(25500) - (350)²]
- √(50 × 5000)
- √250000 = 500

r = a / b = 500 / 500 = 1.00

Final Answer:
The correlation coefficient is 1.00, indicating a perfect positive linear relationship between study hours and exam scores.

Congratulations, you've just learned Pearson Correlation Coefficient!

Bonus: Applications in AI/ML

1. Multicollinearity Detection: In regression models, highly correlated independent variables can cause problems. Correlation matrices help identify and remove redundant features.

2. Time Series Analysis: Identifying lagged correlations to predict future values based on past patterns.

3. Market Analysis: Stock prices, cryptocurrency trends, and economic indicators use correlation to identify trading opportunities and portfolio diversification.

4. Recommendation Systems: Collaborative filtering uses correlation to find similar users or items. “Users who liked X also liked Y” is based on correlation patterns.

[PRwalli @PRwalli]

@rushikesh_agre_ Hi @rushikesh_agre_ is it safe to venture out towards Peddar Road by car? And BKC in the afternoon? How does the day look? I have meetings and want to plan accordingly

[PRwalli @PRwalli]

@rushikesh_agre_ What's the forecast for tomorrow??

[PRwalli @PRwalli]

@rushikesh_agre_ Thank you for your updates! Can always rely on your predictions!! Wishing you plenty of rest! ✨🤞🏻

[News18 @CNNnews18]

When Science Meets Self-Care

Meet public health expert and entrepreneur Tanya Khubchandani who is on a mission to help you live smarter, not harder!

She talks about her wellness centre that works on science-led path to achieve total wellness on #TheBreakfastClub

@toyasingh @kritsween | #PersonOfInterest #Wellness #SelfCare #Serenity #Health

[PRwalli @PRwalli]

@shydev69 Check out @lewagonindia for their web development and ai course! Too good :)

[Mudrika @MudrikaKavdia]

I once met a man who told me he hadn’t been hugged in months.
Not touched.
Not held.
Just work. Sleep. Repeat.
He laughed when he said it.
But that kind of loneliness doesn’t sound funny to me.
Are there any people in this situation?

[real iris @111ris_]

Want this in 6’2

[PRwalli @PRwalli]

What the actual hell is going on @MumbaiPolice @MTPHereToHelp @mybmc stuck here since 20 mins and haven't moved an inch! #mumbaitraffic #mumbaitrafficpolice

[PRwalli @PRwalli]

Why do all epiphanies only happen when you're running on the treadmill or taking a shower? #foodforthought

[PRwalli @PRwalli]

@khushi218 Try Small World by @sauravarya . Not a restaurant but a great place to host events.

[Incognito @Incognito_qfs]

Gandhi was wrong.

[PRwalli @PRwalli]

@rushikesh_agre_ Not really... It's raining in Ghatkopar East