"Constructing a frequency distribution and a histogram"
Shopping Times Analysis
Overview
- This document concerns the shopping times (in minutes) for 18 customers at a grocery store.
- The purpose is to create a grouped frequency distribution and a histogram of the data.
Data Summary
- Data Set: Shopping times (in minutes) recorded for 18 shoppers:
- 21, 15, 30, 23, 17, 25, 37, 26, 35, 28, 27, 34, 38, 24, 18, 21, 31, 32
Part (a): Constructing a Grouped Frequency Distribution
Class Width: Not specified; typically represented as a range (e.g., 5-, 10-minute intervals).
Grouped Frequency Distribution Table:
Class Interval Frequency 15 to 20 3 21 to 26 6 27 to 32 5 33 to 38 4
Explanation of Grouped Frequencies:
- 15 to 20 minutes: 3 shoppers spent between 15 and 20 minutes.
- 21 to 26 minutes: 6 shoppers spent between 21 and 26 minutes.
- 27 to 32 minutes: 5 shoppers spent between 27 and 32 minutes.
- 33 to 38 minutes: 4 shoppers spent between 33 and 38 minutes.
Part (b): Constructing a Histogram
Histogram Visualization:
A graphical representation of the frequency distribution with class intervals on the x-axis and frequency on the y-axis.
The height of the bars represents the number of shoppers in each class interval:
Steps to Create Histogram:
Label the x-axis with the class intervals (15-20, 21-26, etc.).
Label the y-axis with frequencies (0 to max frequency).
Draw bars for each class interval:
- Bar for 15-20: Height = 3
- Bar for 21-26: Height = 6
- Bar for 27-32: Height = 5
- Bar for 33-38: Height = 4
Final Note
- This exercise demonstrates how to summarize data distributions using frequency tables and histograms, crucial for statistical analysis and interpretation. Understanding these concepts helps analyze consumer behavior in a real-world context.