Beta
Data Scientist Associate
Example Practical Exam Solution
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Use this template to complete your analysis and write up your summary for submission.
Task 1
The dataset contains 200 rows and 9 columns with missing values before cleaning. I have validated all the columns against the criteria in the dataset table:
- Region: Same as description without missing values, 10 Regions.
- Place name: Same as description without missing values.
- Rating: 2 missing values, so I replace the missing values with 0.
- Reviews: 2 missing values, so I replace the missing values with overall median number.
- Price: Same as description without missing values, 3 categories.
- Delivery option: Same as description without missing values.
- Dine in option: 50+ missing values, so I replace missing values with 'False', and convert it into boolean data type.
- Take out option: 50+ missing values, so I replace missing values with 'False',and convert it into boolean data type.
After the data validation, the dataset contains 200 rows and 9 columns.
Original Dataset
# Data Validation
# Check all variables in the data against the criteria in the dataset above
import pandas as pd
import matplotlib.pyplot as plt
import matplotlib.style as style
import seaborn as sns
import numpy as np
df = pd.read_csv('data/coffee.csv')
df.info()Validate the categorical variables
cat = ['Region','Place type','Price','Delivery option','Dine in option','Takeout option']
for column in cat:
print(df[column].value_counts())Validate the numerical variables
df.describe()Check the missing values in the columns
df.isna().sum()Clean Rating and Review columns
df['Rating'] = df['Rating'].fillna(0)
median = np.median(df['Reviews'].dropna())
df['Reviews'] = df['Reviews'].fillna(median)
df.info()Clean Dine in Option and Takeaway Option column
df['Dine in option'] = df['Dine in option'].fillna(False)
df['Takeout option'] = df['Takeout option'].fillna(False)
df['Dine in option'] = df['Dine in option'].astype('bool')
df['Takeout option'] = df['Takeout option'].astype('bool')
df.info()Task 2
From Graph 1 Count of Rating, the most number of stores were given rating 4.6, then follows by 4.7. We can see the majority of the stores were given rating higher than 4.5.