Statistical Inference Solutions: Estimation and Hypothesis Testing

Q1 True/False (each needs a quick justification)

Q1(a) Binomial(100, 0.2) approximated by Normal N(20,16)

Steps:

  1. Identify: X ~ Bin(n=100, p=0.2).

  2. Compute mean: μ = np = 100(0.2) = 20.

  3. Compute variance: σ² = np(1−p) = 100(0.2)(0.8) = 16.

  4. Rule: For large n, Binomial ≈ Normal with same mean/variance (CLT-ish approximation).

  5. Conclusion: Yes, approximate with N(20,16).

Q1(b) MAP estimator equals argmax log posterior

Steps:

  1. MAP definition: θ̂MAP = argmaxθ f(θ|x).

  2. Taking log does not move the maximizer

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Essential Templates for Data Visualization Reporting

Line Graph Analysis Template

  • The line graph illustrates trends in [subject] over a [time period] from [start date] to [end date]. The data is measured in [units] and demonstrates [general observation].
  • Overall, the most significant trend is the [adjective] [increase/decrease] in [main subject]. While [item A] showed substantial growth, [item B] experienced considerable fluctuation. The period witnessed [item C] consistently [outperforming/underperforming] other categories.
  • Beginning with [item A],
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Geometry Fundamentals and Logic Principles

Chapter 1: Foundations of Geometry

1.1: Points, Lines, and Planes

  • Collinear: Points on the same line.
  • Coplanar: Points that lie in the same plane.
  • Segment: A part of a line consisting of two endpoints and all points between them.
  • Endpoint: A point at the end of a segment or the starting point of a ray.
  • Ray: Part of a line that extends from one endpoint infinitely in one direction.
  • Opposite rays: Two rays that have a common endpoint and form a line.
  • Postulate: A statement that is accepted as true without
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Engineering Investment Evaluation: Present, Future & Annual Worth

Present, Future & Annual Equivalent — Equal & Unequal Lives

1. Purpose of Investment Evaluation

Used to compare different engineering projects based on their economic worth.

Projects may have:

  • Different lifetimes
  • Different cash-flow patterns
  • Different initial investments

Goal → Select the economically best alternative.

2. Interest Factors (Essential)

(These appear multiple times, so memorize.)

Let i = interest rate per period, n = number of periods.

(P/F, i, n)

Present worth of single future sum:

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Geospatial Data Models and Coordinate Systems Explained

Geospatial Data Models and Acquisition

The Spaghetti Data Model lacks essential spatial relationships such as connectivity (chaining), adjacency (left/right), or containment (e.g., Polygon X within Polygon Y).

Elements of GIScience: Geospatial Data

Geospatial analysis relies on two primary data types:

  • Vector Data: Represents discrete objects with distinct boundaries.
  • Raster Data: Represents continuous fields where every location has a value.

Data Acquisition Methods

Data acquisition involves obtaining

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dd

JULIOL 2018 A 1. A) par 1: a recent… B) par 3: the academics… 2. A)F acros moderns populations… B)F During the 1882… C)F the academics referred… 3. Harsh, hardship, Underpinnings, outlive 4. B,a,c.

JULIOL 2018 B 1. A)par 2: companies Whose… B) par 3: currently, there… 2. A)F 250 bottles… B)F “We found… C)F people in developing… 3.Concerning, Investigation, meet, pervasive 4. A,b,b.

JUNY 2018 A 1.A) par 3:“We have Demonised… B) par 5:There is still no… 2. A)F somewhere

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