Weighted sampling

Analyzing Survey Data in Python

EbunOluwa Andrew

Data Scientist

What is weighted sampling?

Unequal probabilities
Allows researchers to correct issues during data collection

Scales of Justice on table, Weight Scale, Balance

Weighted sampling common variables

Demographic characteristics like gender, age, location, and education
Account for differences between those who do or do not partake in research studies

Family, people of different ages outline style

Cell-based weighting

¹ https://www.geopoll.com/blog/weighting-survey-data-raking-cell-weighting/

Cell based-weighting

¹ https://www.geopoll.com/blog/weighting-survey-data-raking-cell-weighting/

Cell based-weighting

¹ https://www.geopoll.com/blog/weighting-survey-data-raking-cell-weighting/

Cell based-weighting

¹ https://www.geopoll.com/blog/weighting-survey-data-raking-cell-weighting/

Analyzing youth spending patterns with Python

yp_survey

| Gender | Age | Entertainment |
|--------|-----|---------------|
| female |  19 | Agree         |
| female |  20 | Agree         |
| male   |  19 | Agree         |
| female |  19 | Disagree      |
| female |  24 | Disagree      |
| male   |  18 | Agree         |
| male   |  18 | Agree         |
| male   |  20 | Disagree      |

Analyzing youth spending patterns with Python

import pandas as pd
yp_crosstab = pd.crosstab(
  yp_survey['Gender'],
  yp_survey['Entertainment'])
yp_crosstab

yp_crosstab.plot.barh()

|        | Agree | Disagree |
|--------|-------|----------|
| female |    81 |       84 |
| male   |    84 |       46 |

Analyzing youth spending patterns with Python

survey = yp_survey.groupby(['Gender', 'Entertainment'])['Age'].count().reset_index()

survey.columns = ['Gender', 'Entertainment', 'Respondents']
survey

| Gender | Entertainment | Respondents |
|--------|---------------|-------------|
| female | Agree         |          81 |
| female | Disagree      |          84 |
| male   | Agree         |          84 |
| male   | Disagree      |          46 |

Analyzing youth spending patterns with Python

survey['% total respondents'] = survey.Respondents * 100./survey.Respondents.sum()

survey['% of population'] = [35, 25, 20, 20]

survey['Weight'] = survey['% of population']/survey['% total respondents']

survey['Weighted Respondents'] = survey.Weight * survey.Respondents

Analyzing youth spending patterns with Python

survey[['Gender','Entertainment',
        'Respondents','Weighted Respondents']].set_index(
  ['Gender','Entertainment']).plot.barh()

Let's practice!

Analyzing Survey Data in Python