Essential Of Probability
Assignment ~ Week 10
1 About Probability
Probability theory stands as the cornerstone of statistical inference, providing the mathematical framework to measure and manage uncertainty. Whether predicting industrial performance, clinical results, or financial outcomes, probability helps quantify how likely various results may occur.
This document explores essential probability concepts:
- Fundamental Concept
- Independent & Dependent Events
- Exclusive & Exhaustive Events
- Union of Events
- Binomial Experiment
- Binomial Distribution
2 Fundamental Concept
Detailing the methodology for calculating basic likelihoods, the video uses elementary scenarios like coin tosses to illustrate key probabilistic principles. The material highlights the mathematical foundations necessary for all subsequent probability topics:
- Simple Probability
- Sample Space
- Complement Rule
2.1 Simple Probability
Interpretation:
Probability can be defined as the chance of an event occurring by
calculating the number of desired outcomes with the total number of
possibilities on a scale of 0 to 1, where a value of 1 means that the
probability is very accurate and vice versa.
Formula:
\[P = \frac{\text{Total Number Of Favourable
Outcomes}}{\text{Total Number Of Possible Outcomes}}\]
Example: Probability of drawing a Queen from a deck of cards.
# Definisikan Ruang Sampel (Total Kartu)
Total_Cards <- 52
# Definisikan Kejadian A: Mendapatkan kartu Queen (ada 4 Queen)
Favourable_Outcomes_A <- 4
# Hitung Probabilitas P(A)
P_A_Queen <- Favourable_Outcomes_A / Total_Cards
# Tampilkan Hasil
cat("Total Cards:", Total_Cards, "\n")## Total Cards: 52
## Favourable Outcomes (Queen): 4
## Probability P(Queen): 0.0769
2.2 Sample Space
Interpretation:
The Sample Space is the set of all possible outcomes of a random
experiment. It defines the entire universe of possible results.
(Insert sample space Venn diagram image here if needed)
Formula (Conceptual):
Sample Space:
\[S = \{h_1, h_2, ..., h_n\}\]
Total Outcomes:
\[N = |S|\]
Note:
\(h_n\) is the n-th individual outcome,
and \(|S|\) represents the total number
of possible outcomes (Total Outcomes), denoted by N.
Example: Sample Space of rolling two six-sided dice.
# Ruang Sampel (S) saat melempar dua dadu (dadu 1, dadu 2)
# Setiap hasil adalah pasangan terurut (d1, d2).
# Total kemungkinan hasil: 6 * 6 = 36
Total_Outcomes_N_Dice <- 6 * 6
# Contoh beberapa hasil dalam ruang sampel S
Example_Outcomes <- c("(1, 1)", "(1, 2)", "(2, 1)", "(6, 6)")
# Tampilkan hasil
cat("Example Outcomes in S:", Example_Outcomes, "\n")## Example Outcomes in S: (1, 1) (1, 2) (2, 1) (6, 6)
## Total Outcomes (N) for Two Dice: 36
2.3 Complement Rule
Interpretation:
The Complement Rule states that the probability of an event not
happening is equal to1 minus the probability of the event
happening.
The complement of event A is written as
A′ (A prime) or Aᶜ.
This rule is useful when calculating probabilities of events that are easier to evaluate by first determining what does not occur.
Formula:
\[
P(A') = 1 - P(A)
\]
Example: Probability of not drawing a Queen from a standard deck of 52 cards.
# Probabilitas menggunakan Aturan Komplemen (Complement Rule)
# Probabilitas mendapatkan Queen (ada 4 Queen dari 52 kartu)
P_Queen <- 4 / 52
# Aturan komplemen: probabilitas TIDAK mendapatkan Queen
P_Not_Queen <- 1 - P_Queen
# Tampilkan hasil
cat("P(Queen):", round(P_Queen, 4), "\n") # Menampilkan peluang mendapatkan Queen## P(Queen): 0.0769
## P(Not Queen): 0.9231