Mengukur sebuah sampel

Mari bekerja dengan sampel pelemparan koin untuk menghitung beberapa probabilitas. Anda akan menghitung frekuensi absolut dan relatif serta memeriksa nilai teoretis dari sebaran data sampel.

Array sample_of_two_coin_flips memiliki 1.000 percobaan, masing-masing terdiri dari dua lemparan koin adil. Untuk setiap percobaan, kita mencatat jumlah sisi gambar (heads) dari dua lemparan koin: 0, 1, atau 2.

Objek binom serta metode find_repeats() dan relfreq() dari pustaka scipy.stats telah dimuatkan untuk Anda. Anda akan memerlukannya untuk menghitung probabilitas dalam latihan ini.

Latihan ini adalah bagian dari kursus

Dasar-Dasar Probabilitas di Python

Latihan interaktif praktis

Cobalah latihan ini dengan menyelesaikan kode contoh berikut.

# Count how many times you got 2 heads from the sample data
count_2_heads = ____(sample_of_two_coin_flips).counts[2]

# Divide the number of heads by the total number of draws
prob_2_heads = count_2_heads / ____

# Display the result
print(prob_2_heads)

Edit dan Jalankan Kode

Latihan ini adalah bagian dari kursus

Dasar-Dasar Probabilitas di Python

SkillTag.level.intermediateSkillTag.label

4.8+

Mulai Kursus Gratis

A coin flip is the classic example of a random experiment. The possible outcomes are heads or tails. This type of experiment, known as a Bernoulli or binomial trial, allows us to study problems with two possible outcomes, like “yes” or “no” and “vote” or “no vote.” This chapter introduces Bernoulli experiments, binomial distributions to model multiple Bernoulli trials, and probability simulations with the scipy library.

Exercise 1: Let’s flip a coin in Python Exercise 2: Flipping coins Exercise 3: Using binom to flip even more coins Exercise 4: Probability mass and distribution functions Exercise 5: Predicting the probability of defects Exercise 6: Predicting employment status Exercise 7: Predicting burglary conviction rate Exercise 8: Expected value, mean, and variance Exercise 9: Calculating the expected value and variance Exercise 10: Calculating the sample mean Exercise 11: Checking the result Exercise 12: Calculating the mean and variance of a sample

In this chapter you'll learn to calculate various kinds of probabilities, such as the probability of the intersection of two events and the sum of probabilities of two events, and to simulate those situations. You'll also learn about conditional probability and how to apply Bayes' rule.

Exercise 1: Menghitung probabilitas dua kejadian Exercise 2: Ada tumpang tindih?Exercise 3: Mengukur sebuah sampel

Latihan Saat Ini

Exercise 4: Probabilitas gabungan Exercise 5: Setumpuk kartu Exercise 6: Probabilitas bersyarat Exercise 7: Penerbangan tertunda Exercise 8: Tabel kontingensi Exercise 9: Lebih banyak kartu Exercise 10: Hukum probabilitas total Exercise 11: Mesin Formula 1 Exercise 12: Pemilih Exercise 13: Aturan Bayes Exercise 14: Pengkondisian Exercise 15: Pabrik dan suku cadang Exercise 16: Tes darah flu babi

Until now we've been working with binomial distributions, but there are many probability distributions a random variable can take. In this chapter we'll introduce three more that are related to the binomial distribution: the normal, Poisson, and geometric distributions.

Exercise 1: Normal distributions Exercise 2: Range of values Exercise 3: Plotting normal distributions Exercise 4: Within three standard deviations Exercise 5: Normal probabilities Exercise 6: Restaurant spending example Exercise 7: Smartphone battery example Exercise 8: Adults' heights example Exercise 9: Poisson distributions Exercise 10: ATM example Exercise 11: Highway accidents example Exercise 12: Generating and plotting Poisson distributions Exercise 13: Geometric distributions Exercise 14: Catching salmon example Exercise 15: Free throws example Exercise 16: Generating and plotting geometric distributions

No that you know how to calculate probabilities and important properties of probability distributions, we'll introduce two important results: the law of large numbers and the central limit theorem. This will expand your understanding on how the sample mean converges to the population mean as more data is available and how the sum of random variables behaves under certain conditions. We will also explore connections between linear and logistic regressions as applications of probability and statistics in data science.

Exercise 1: From sample mean to population mean Exercise 2: Generating a sample Exercise 3: Calculating the sample mean Exercise 4: Plotting the sample mean Exercise 5: Adding random variables Exercise 6: Sample means Exercise 7: Sample means follow a normal distribution Exercise 8: Adding dice rolls Exercise 9: Linear regression Exercise 10: Fitting a model Exercise 11: Predicting test scores Exercise 12: Studying residuals Exercise 13: Logistic regression Exercise 14: Fitting a logistic model Exercise 15: Predicting if students will pass Exercise 16: Passing two tests Exercise 17: Wrapping up