데이터 분석 공부

콘크리트 내구성 예측 인공신경망 콘크리트 압축 내구력에 대한 데이터 1030개의 콘크리트 예제, 구성요소를 나타내는 8개의 속성으로 이루어져 있음 mount of cement 콘크리트의 총량, slag 슬래그, ahs 회분, water 물superplasicizer 고성능감수제, coarse aggregate 굵은 골재fine aggregate 잔골재, aging time 숙성 시간 1. 데이터 준비와 탐구 > concrete = read.csv("C:/R/concrete.csv", header=T) > str(concrete) 'data.frame':1030 obs. of 9 variables: $ cement : num 141 169 250 266 155 ... $ slag : num 212 42.2..

SQL Project Planning SQL Project Planning | HackerRank Write a query to output the start and end dates of projects listed by the number of days it took to complete the project in ascending order. www.hackerrank.com # Problem You are given a table, Projects, containing three columns: Task_ID, Start_Date and End_Date. It is guaranteed that the difference between the End_Date and the Start_Date is ..

Ollivander's Inventory 문제에 대한 자세한 내용은 다음 링크에서 확인하실 수 있습니다 Ollivander's Inventory | HackerRank Help pick out Ron's new wand. www.hackerrank.com # Problem Harry Potter and his friends are at Ollivander's with Ron, finally replacing Charlie's old broken wand. Hermione decides the best way to choose is by determining the minimum number of gold galleons needed to buy each non-evil wand of high power ..

Challenges Challenges | HackerRank Print the total number of challenges created by hackers. www.hackerrank.com # Problem Julia asked her students to create some coding challenges. Write a query to print the hacker_id, name, and the total number of challenges created by each student. Sort your results by the total number of challenges in descending order. If more than one student created the same..

Placements Placements | HackerRank Write a query to output the names of those students whose best friends got offered a higher salary than them. www.hackerrank.com # Problem You are given three tables: Students, Friends and Packages. Students contains two columns: ID and Name. Friends contains two columns: ID and Friend_ID (ID of the ONLY best friend). Packages contains two columns: ID and Salar..

The Report The Report | HackerRank Write a query to generate a report containing three columns: Name, Grade and Mark. www.hackerrank.com # Problem You are given two tables: Students and Grades. Students contains three columns ID, Name and Marks. Grades contains the following data: Ketty gives Eve a task to generate a report containing three columns: Name, Grade and Mark. Ketty doesn't want the N..

1. The Blunder 2. Population Census 3. African Cities 4. Higher Than 75 Marks HackerRank HackerRank is the market-leading technical assessment and remote interview solution for hiring developers. Learn how to hire technical talent from anywhere! www.hackerrank.com 1. The Blunder 조건 1) salary 값의 평균에서 잘못 계산한 salary의 평균 빼기 조건 2) 올림으로 계산하기 SELECT CEIL(AVG(salary) - AVG(REGEXP_REPLACE(salary, '[0]', ..

1. Employee Names 2. Employee Salaries 3. Revising Aggregations - The Sum Function 4. Revising Aggregations - The Count Function 5. Revising Aggregations - Averages HackerRank HackerRank is the market-leading technical assessment and remote interview solution for hiring developers. Learn how to hire technical talent from anywhere! www.hackerrank.com 1. Employee Names SELECT name FROM employee OR..

1. Revising the Select Query 1 2. Revising the Select Query 2 3. Select All 4. Select By ID 5. Average Population 6. Population Density Difference 7. Japan Population 8. Japanese Cities’ Names 9. Japanese Cities’ Attributes HackerRank HackerRank is the market-leading technical assessment and remote interview solution for hiring developers. Learn how to hire technical talent from anywhere! www.ha..

Titanic 생존자 예측 ② Feature Engineering & 모델링 3. Feature Engineering Feature Engineering을 시작하기에 앞서 상관계수, 결측치를 확인해보자 train.corr() train.isnull().sum() Train과 Test data를 한 번에 변환하기 위해 List에 담아주었다. data_list = [train, test] 3-1. Sex Sex는 male(남성), female(여성)으로 나누어져 있다. 이를 0과 1로 변경해주자 # int type의 숫자 0과 1로 매핑 for data in data_list: data['Sex'] = data['Sex'].astype('category').cat.codes train['Sex'].head(..