Statistika deskriptif dan function masking

Sebelumnya, Anda telah melihat bahwa fungsi summary() menghitung mean, median, kuartil ke-1 dan ke-3, serta nilai minimum dan maksimum. Simpangan baku tidak disertakan. Namun, paket Hmisc dan psych sama-sama memiliki fungsi describe() yang menyediakan lebih banyak statistika deskriptif termasuk simpangan baku.

Untuk mendapatkan statistika deskriptif ini, Anda akan menjalankan fungsi describe() yang memiliki nama sama di kedua paket. Untuk menghindari kebingungan, Anda sebaiknya selalu menggunakan notasi namapaket::namafungsi() untuk secara eksplisit menentukan fungsi dari paket yang Anda inginkan.

Himpunan data abaloneKeep dan paket dplyr sudah dimuat untuk Anda.

Latihan ini adalah bagian dari kursus

R untuk Pengguna SAS

Petunjuk latihan

Muat paket Hmisc.
Dapatkan statistik deskriptif untuk jenis kelamin, panjang, diameter, dan tinggi abalone menggunakan fungsi Hmisc::describe().
Muat paket psych - perhatikan peringatan tentang fungsi describe() yang dimasking dari paket Hmisc (karena kedua paket memiliki fungsi describe() yang sama).
Jalankan fungsi describe() dari paket psych untuk mendapatkan statistik deskriptif untuk panjang, diameter, dan tinggi abalone. Jangan sertakan variabel jenis kelamin karena psych::describe() hanya berfungsi untuk variabel numerik.

Latihan interaktif praktis

Cobalah latihan ini dengan menyelesaikan kode contoh berikut.

# Load the Hmisc package
library(___)

# Run describe() from Hmisc for sex, length, diameter, height
abaloneKeep %>% 
  select(___, ___, ___, ___) %>% 
  ___::___

# Load the psych package
___

# Run describe() from psych for length, diameter, height
___ %>% 
  ___ %>% 
  ___::___

Edit dan Jalankan Kode

Latihan ini adalah bagian dari kursus

R untuk Pengguna SAS

SkillTag.level.beginnerSkillTag.label

4.8+

Mulai Kursus Gratis

This first chapter will get you oriented into the R programming environment. You'll learn how to get help, load a dataset, and increase functionality by adding packages. You'll begin working with the abalone dataset (through the dplyr package workflow) to get descriptive statistics and create helpful visualizations (using the ggplot2 package).

Exercise 1: Get help and load data in R Exercise 2: Getting help Exercise 3: Load dataset and get details Exercise 4: Add functionality with packages Exercise 5: Dataset contents and descriptive statistics Exercise 6: Load external dataset Exercise 7: Dataset contents Exercise 8: Descriptive statistics Exercise 9: Graphical visualizations Exercise 10: Histograms Exercise 11: Boxplots and violin plots Exercise 12: Scatterplots

Now that you are oriented in the R environment, this chapter will advance your understanding of R's versatility working with data objects. You'll learn how to create and modify variables in the abalone data set. Using your ggplot2 visualization skills, you will discover the data errors in the abalone data and then create a final cleaned data set ready for analysis and modeling.

Exercise 1: Objects - the building blocks of R Exercise 2: Create data objects in R Exercise 3: Create composite object types Exercise 4: Selecting elements from objects Exercise 5: Determine variable types Exercise 6: Select elements in objects Exercise 7: Manipulating datasets and data objects Exercise 8: Create new variables Exercise 9: Recode variables Exercise 10: Object type conversion Exercise 11: Data quality and cleaning Exercise 12: Variables inspection Exercise 13: Illogical weights Exercise 14: Check dimension measurements Exercise 15: Check final dataset

Once your data set has been cleaned, the next step is exploration. In chapter 3 you will learn how to compute descriptive statistics, explore associations (e.g., correlations) among the variables, and perform bi-variate statistical tests (e.g., t-tests and chi-square tests). You will also create graphical visualizations which illustrate the bi-variate associations and group comparison tests.

Exercise 1: Analisis data eksploratori Exercise 2: Statistika deskriptif dan function masking

Latihan Saat Ini

Exercise 3: Statistik spesifik untuk satu atau lebih variabel Exercise 4: Statistik ringkasan per grup Exercise 5: Korelasi dan uji t Exercise 6: Korelasi bivariat Exercise 7: Diagram Sebar Exercise 8: Korelasi menurut jenis kelamin Exercise 9: Uji untuk dua kelompok Exercise 10: Data kategorikal: analisis dan visualisasi Exercise 11: Uji chi-square Exercise 12: Plot mosaik Exercise 13: Kategori usia menurut kategori berat cangkang

In this final chapter, you will learn how to work with one of the most versatile data object types in R called a list. These skills will enable you to save and manipulate your output from descriptive statistics, associations, and group comparison computations. You will also learn how to perform ANOVA (analysis of variance) and linear regression in R. All your skills are put to use in the final exercises to create the best models for predicting abalone ages from their sex, size, and weight measurements.

Exercise 1: Working with output objects Exercise 2: Descriptive statistics output Exercise 3: Summarise output Exercise 4: Group_by output Exercise 5: Working with lists Exercise 6: Hmisc describe output Exercise 7: Correlations output Exercise 8: t-tests output Exercise 9: Chi-square tests output Exercise 10: ANOVA and linear models Exercise 11: ANOVA Exercise 12: Linear regression Exercise 13: Final models evaluation Exercise 14: Abalone age predictors Exercise 15: Best model by sex Exercise 16: Course summary and recommendations