Does going to university in a different country affect your mental health? A Japanese international university surveyed its students in 2018 and published a study the following year that was approved by several ethical and regulatory boards.
The study found that international students have a higher risk of mental health difficulties than the general population, and that social connectedness (belonging to a social group) and acculturative stress (stress associated with joining a new culture) are predictive of depression.
Explore the students data using PostgreSQL to find out if you would come to a similar conclusion for international students and see if the length of stay is a contributing factor.
Here is a data description of the columns you may find helpful.
| Field Name | Description |
|---|---|
inter_dom | Types of students (international or domestic) |
japanese_cate | Japanese language proficiency |
english_cate | English language proficiency |
academic | Current academic level (undergraduate or graduate) |
age | Current age of student |
stay | Current length of stay in years |
todep | Total score of depression (PHQ-9 test) |
tosc | Total score of social connectedness (SCS test) |
toas | Total score of acculturative stress (ASISS test) |
-- Run this code to save the CSV file as students
SELECT *
FROM 'students.csv';Task 1: Count all records, count all records per student type
-- Count of all records
SELECT COUNT(*) AS count_of_all_records
FROM 'students.csv';-- Count all records per student type
SELECT inter_dom,COUNT(inter_dom) AS count_per_student
FROM 'students.csv'
GROUP BY inter_dom;Task 2: Filter data to see how it differs between student types
-- Queries will be grouped by academic level, gender, region, inter/dom status
-- Academic level
SELECT academic,
ROUND(AVG(age),2) AS avg_age_per_level,
ROUND(AVG(japanese),2) AS avg_jap_score_per_level,
ROUND(AVG(english),2) AS avg_eng_score_per_level
FROM 'students.csv'
GROUP BY academic
ORDER BY academic;-- Gender
SELECT gender,
ROUND(AVG(age),2) AS avg_age_per_level,
ROUND(AVG(japanese),2) AS avg_jap_score_per_level,
ROUND(AVG(english),2) AS avg_eng_score_per_level
FROM 'students.csv'
GROUP BY gender
ORDER BY gender;-- Region
SELECT region,
ROUND(AVG(age),2) AS avg_age_per_level,
ROUND(AVG(japanese),2) AS avg_jap_score_per_level,
ROUND(AVG(english),2) AS avg_eng_score_per_level
FROM 'students.csv'
GROUP BY region
ORDER BY region;-- Inter/Dom
SELECT inter_dom,
ROUND(AVG(age),2) AS avg_age_per_level,
ROUND(AVG(japanese),2) AS avg_jap_score_per_level,
ROUND(AVG(english),2) AS avg_eng_score_per_level
FROM 'students.csv'
GROUP BY inter_dom
ORDER BY inter_dom;Task 3: Summary Statistics of diagnostic tests
-- Depression Score
SELECT ROUND(MIN(todep),2) AS min_dep_score,
ROUND(MAX(todep),2) AS max_dep_score,
ROUND(AVG(todep),2) AS avg_dep_score
FROM 'students.csv';-- Social Connectedness
SELECT ROUND(MIN(tosc),2) AS min_sc_score,
ROUND(MAX(tosc),2) AS max_sc_score,
ROUND(AVG(tosc),2) AS avg_dsc_score
FROM 'students.csv';