sawo11 님의 블로그

목적클러스터별 특징 확인을 통한 전략 방향성 도출 가설예비 우수 판매자들은 관심 필요 판매자보다 상품의 평균 가격이 더 높을 것이다.집단 A: 예비 우수 판매자 (클러스터 3)집단 B: 관심 필요 판매자 (클러스터 0) 검정 방법 선택 과정가설: 예비 우수 판매자들은 관심 필요 판매자보다 상품의 평균 가격이 더 높을 것이다.종속변수: 상품의 평균 가격 (연속형)독립변수: 예비 우수 판매자, 관심 필요 판매자 (범주형, 그룹 2개, 독립표본)            ⇒ 정규성 검정을 통해 2 sample T-test 와 Mann-Whitney 중 선택해야함 정규성 검정# 집단 나누기group_a = merge_df[merge_df['군집'] == 3]['판매가']group_b = merge_df[merge_d..

Given a table of Facebook posts, for each user who posted at least twice in 2021, write a query to find the number of days between each user’s first post of the year and last post of the year in the year 2021. Output the user and number of the days between each user's first and last post.p.s. If you've read the Ace the Data Science Interview and liked it, consider writing us a review?posts Table..

This is the same question as problem #3 in the SQL Chapter of Ace the Data Science Interview!Assume you're given the table on user viewership categorised by device type where the three types are laptop, tablet, and phone.Write a query that calculates the total viewership for laptops and mobile devices where mobile is defined as the sum of tablet and phone viewership. Output the total viewership ..

Tesla is investigating production bottlenecks and they need your help to extract the relevant data. Write a query to determine which parts have begun the assembly process but are not yet finished.Assumptions:parts_assembly table contains all parts currently in production, each at varying stages of the assembly process.An unfinished part is one that lacks a finish_date.This question is straightfo..

Assume you're given two tables containing data about Facebook Pages and their respective likes (as in "Like a Facebook Page").Write a query to return the IDs of the Facebook pages that have zero likes. The output should be sorted in ascending order based on the page IDs.pages Table: ColumnNameTypepage_namevarcharpage_idintegerpages Example Input:page_idpage_name20001SQL Solutions20045Brain Exerc..

Given a table of candidates and their skills, you're tasked with finding the candidates best suited for an open Data Science job. You want to find candidates who are proficient in Python, Tableau, and PostgreSQL.Write a query to list the candidates who possess all of the required skills for the job. Sort the output by candidate ID in ascending order. Assumption:There are no duplicates in the can..

Assume you're given a table Twitter tweet data, write a query to obtain a histogram of tweets posted per user in 2022. Output the tweet count per user as the bucket and the number of Twitter users who fall into that bucket.In other words, group the users by the number of tweets they posted in 2022 and count the number of users in each group.tweets Table: ColumnNameTypetweet_idintegeruser_idinteg..

주말에 다시 한번 복습하며 작성하는 QCC 오답 🌧️문제1 (X)2012년 이후 개봉한 영화 중, 장르가 2개 이상 포함된 영화의 연도별 매출을 구하는 SQL 문을 작성해주세요. 단, 해당 영화는 최소 100개 이상의 평점 수를 받은 경우만 결과에 포함해주세요. 결과는 개봉 연도를 기준으로 오름차 정렬해야 합니다.SELECT release_year, SUM(revenue) revenue -- 연도별 매출이므로 SUMFROM moviesWHERE release_year >= 2012AND JSON_LENGTH(genres) >= 2AND vote_count >= 100 GROUP BY release_yearORDER BY release_year ;JSON_LENGTH(*) 함수: JSON 객체나 배열의..