Notes, summaries, assignments, exams, and exercises for Mathematics for Baccalaureate

Karl Pearson Correlation Coefficient, Regression Bounds and Chebyshev's Theorem

MathematicsUpdated on 4.73 KB

Calculating Karl Pearson Correlation Coefficient

Question 11: Calculate the coefficient of correlation from the following data:

X12981011137
Y1486911123

To calculate Karl Pearson's coefficient of correlation (r), we use the formula:

r = ∑dx·dy / √(∑dx2 × ∑dy2)

Where:

  • dx = X - X̄
  • dy = Y - Ȳ

Step 1: Find the Means

First, calculate the mean of X (X̄) and Y (Ȳ):

X̄ = (12 + 9 + 8 + 10 + 11 + 13 + 7) / 7 = 70 / 7 = 10

Ȳ = (14 + 8 + 6 + 9 + 11 + 12 + 3) / 7 = 63 / 7 = 9

Step 2: Prepare the Calculation Table

XYdx = X - 10dy = Y - 9dx2dy2dx·dy
12142542510
98-1-1111
86-2-3496
10900000
111112142
131233999
73-3-693618
Total288446

Step 3: Substitute into the Formula

Substitute the sums from the table into the correlation formula:

r = 46 / √(28 × 84)
r = 46...

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Statistical Learning and Linear Regression: Key Notes and Formulas

MathematicsUpdated on 7.23 KB

Introduction to Statistical Learning

Key Notation

  • Y: Response (dependent/output) variable - quantitative or qualitative
  • X₁,...,Xₚ: Predictors (features/covariates/independent variables)
  • p: Number of predictors
  • n: Number of observations
  • i: Subject index (i = 1,...,n)
  • j: Variable index (j = 1,...,p)
  • Data: (Yᵢ, Xᵢ), i = 1,...,n

Types of Learning

  • Supervised learning: Have both Y and X (prediction or inference) - PRIMARY FOCUS
  • Unsupervised learning: Have X but no Y

Model for Data

Yᵢ = f(Xᵢ) + εᵢ, i = 1,...,n
Assumptions: E(εᵢ) = 0, var(εᵢ) = σ², εᵢ are mutually independent
Properties: E(Yᵢ|Xᵢ) = f(Xᵢ), var(Yᵢ|Xᵢ) = σ²

Prediction vs Inference

PredictionInference
ˆY = ˆf(X)Understand relationship between Y and X
ˆf can be black
...
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Numerical Linear Algebra: Floating-Point Stability, Solvers and SVD (Study Notes)

MathematicsUpdated on 2.78 MB

Floating-Point Arithmetic and Stability

wCgqVXThjkjFQAAAABJRU5ErkJggg==

Eigendecomposition: Symmetric & Positive Definite (PD)

Exponent bias: b = 011111111111 = 1023

Grampian matrix: 8Coj0fVISuIFQAAAAASUVORK5CYII=

Maximum exponent: maxp = 1023 v0fN56DRlPBFnMAAAAASUVORK5CYII=

Minimum exponent: minp = -1023 - 51

L2 Induced Matrix Norm: tGTqpQ1MsAAAAASUVORK5CYII=

8AA5DM53COpDsAAAAASUVORK5CYII= DzmtbcOUm1CWAAAAAElFTkSuQmCC

Precision range: 2**-52 <= s < 2

Note on stability: A stable algorithm cannot overcome an ill-conditioned system; it can only guarantee precision when the system is not ill-conditioned.

Special Floating-Point Values:

  • np.Inf: 0111111111110
  • np.NaN: 0111111111111
  • np.Inf - np.Inf: NaN
  • np.Inf / np.Inf: NaN
  • np.Inf * 0: NaN
  • np.NaN + any: NaN

Backward Error: Back-calculating from the computed result to find the equivalent perturbation of the input.

Analytical inverse and the Woodbury matrix identity are both effective...

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Matrices: multiplication, rank, determinant, inverse and Rouche-Frobenius theorem

Mathematics155.53 KB

System Types
The systems of equations can be
classified by the number of solutions that can arise. According to that case may have the following cases:
· Incompatible system if it has no solution.
· Compatible system if you have any solution in this case can also distinguish between:
or compatible system determined when it has a finite number of solutions.
indeterminate
or compatible system when it admits an infinite set of solutions.
Fitting and classification:
Image
Calculating the rank of a matrix for determining
Image
1. We can rule a line if:.
· All the coefficients are zeros.
· There are two equal lines.
• A line is proportional to another.
• A line is a linear combination of others.
Delete the third column because it is a linear...

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SPSS Essentials: Data Analysis and Statistical Computing

Mathematics4.15 KB

SPSS (Statistical Package for the Social Sciences) is a software tool used for data analysis, statistical tests, and visualization. It is widely used in research, business, and academia for handling both small and large datasets.

Understanding SPSS: Purpose and Capabilities

The primary purpose of SPSS is to simplify and streamline data management and analysis. It allows users to:

  • Perform statistical calculations without complex coding.
  • Generate graphs, tables, and charts for data representation.

Key Applications of SPSS Software

SPSS is applicable in multiple fields for various purposes:

  • Research: Analyze survey or experimental data.
  • Education: Evaluate student and staff performance.
  • Healthcare: Track patient records or treatment effectiveness.
  • Marketing:
...
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Bernini's St. Peter's Colonnade: Baroque Design & Symbolism

Mathematics3.32 KB

The Colonnade of St. Peter's Basilica

A masterpiece of Baroque urban design by Gian Lorenzo Bernini.

Historical Context and Style

  • Timeline: De Lany 1656–1667.
  • Style: High Baroque (Distillation Baroque).
  • Architect: Gian Lorenzo Bernini.
  • Building System: Architrave.
  • Location: Vatican City (Rome).

Architectural Elements and Structure

The colonnade supports an entablature surmounted by a balustrade and a large collection of statues. The structure is composed of four rows of Doric columns, which are more slender than usual, topped with an Ionic entablature. The 296 columns form a seemingly endless forest, wisely separating the square from the exterior without a harsh break.

The colonnade is crowned with a balustrade housing 140 statues of saints.

Spatial

...
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Vocabulary Builder: 35 Essential Words with Definitions

Mathematics3.28 KB

Vocabulary Builder: 35 Essential Words

A

1. Agonized

Manifesting, suffering, or characterized by great physical or mental pain.

2. Ample

Large and accommodating.

3. Assent

The expression of approval or agreement.

B

4. Befall

(Of something bad) happen to someone.

C

5. Chariots

A two-wheeled horse-drawn vehicle used in ancient warfare and racing.

6. Conceive

Become pregnant with (a child). Form or devise (a plan or idea) in the mind.

7. Cordial

Friendly, warm.

D

8. Dews

Moisture condensed from the atmosphere, especially at night, and deposited in the form of small drops upon any cool surface.

9. Divine

Of, from, or like God or a god.

10. Doe

Female deer.

F

11. Foe

An enemy or opponent.

G

12. Gossamer

Used to refer to something very light, thin, and insubstantial or delicate....

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Calculating Probabilities from a Table

Mathematics2.5 KB

Worksheet: Revisiting Calculating Probabilities from a Table

1. Goals

G: GradesP: PopularS: SportsTotals
B: Boy1175060227
F: Girl1309130251
Totals24714190| 478

P(F) = 251/478 = 0.525

The probability that a randomly selected student is a girl is 0.525.

P(PC) = (247 + 90)/478 = (478 – 141)/478 = 337/478 = 0.705

The probability that a randomly selected student did not indicate being popular as a primary goal is 0.705.

P(B or S) = (227 + 90 – 60)/478 = 257/478 = 0.538

The probability that a randomly selected student is a boy or indicated a primary goal is to excel at sports or both is 0.538.

P(B and S) = 60/478 = 0.126

The probability that a randomly selected student is a boy and indicated a primary goal is to excel at sports is 0.126.

P(S|B) = 60/227 =...

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Programmer Position Application and Gone Girl Novel Review

Mathematics2.67 KB

Programmer Position Application

Dear Mr. Gilhooley,

I am writing to apply for the programmer position advertised on your website/in the Times Union on 25 January. As requested, I am enclosing a completed job application, my certification, my resume, and three references.

The opportunity presented in this listing is very appealing to me, and I believe that my strong technical experience and education will make me a very competitive candidate for this position and an asset to your organization. The key strengths that I possess for success in this position include:

  • I have been in charge of 23 people in private banking.
  • I strive for continued excellence.
  • I provide exceptional contributions to customer service for all customers.
  • I am a conscientious person
...
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The Future of Pocket Money: Debit Cards and Financial Management

Mathematics2.36 KB

Pocket money isn’t a controversial topic nowadays.

If there have been a lot of debates over pocket money.

Pocket money used to be a controversial topic.

T

Pocket money has always been a controversial topic.

T

The debate regarding pocket money nowadays is about how much money should be given.

If today’s debate rages about something entirely different.

The debate regarding pocket money nowadays isn’t about how much money should be given.

T

The debate regarding pocket money nowadays is about at what age money should be given.

If

Twelve-year-old will be able to use the new debit card.

A new debit card has just been launched for teenagers as young as 13.

Thirteen-year-olds won’t be able to use the credit card.

Teenagers over 13 will be able to use the...

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