Skip to main content
Ch. 2 - Exploring Data with Tables and Graphs
Triola - Elementary Statistics 14th Edition
Triola14th EditionElementary StatisticsISBN: 9780137366446Not the one you use?Change textbook
Chapter 2, Problem 3.2.23

In Exercises 21–24, find the coefficient of variation for each of the two samples; then compare the variation. (The same data were used in Section 3-1.)


Pulse Rates Listed below are pulse rates (beats per minute) from samples of adult males and females (from Data Set 1 “Body Data” in Appendix B). Does there appear to be a difference?


[IMAGE]

Verified step by step guidance
1
Step 1: Understand the coefficient of variation (CV). The CV is a standardized measure of dispersion of a probability distribution or data set. It is calculated as the ratio of the standard deviation (σ) to the mean (μ), expressed as a percentage: CV = (σ / μ) × 100.
Step 2: Identify the data for the two samples (males and females). Extract the pulse rate data for each group from the provided image or dataset. Ensure you have the mean (μ) and standard deviation (σ) for each group.
Step 3: Calculate the coefficient of variation for the male sample. Use the formula CV = (σ / μ) × 100, where σ is the standard deviation of the male pulse rates and μ is the mean of the male pulse rates.
Step 4: Calculate the coefficient of variation for the female sample. Similarly, use the formula CV = (σ / μ) × 100, where σ is the standard deviation of the female pulse rates and μ is the mean of the female pulse rates.
Step 5: Compare the coefficients of variation for the two samples. A higher CV indicates greater relative variability in the data. Analyze whether the male or female pulse rates exhibit more variation and discuss whether there appears to be a difference in variability between the two groups.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
10m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Coefficient of Variation

The coefficient of variation (CV) is a statistical measure of the relative variability of a dataset. It is calculated as the ratio of the standard deviation to the mean, expressed as a percentage. This metric allows for the comparison of the degree of variation between different datasets, regardless of their units or scales, making it particularly useful in comparing the variability of pulse rates between males and females.
Recommended video:
Guided course
05:43
Correlation Coefficient

Standard Deviation

Standard deviation is a measure of the amount of variation or dispersion in a set of values. A low standard deviation indicates that the values tend to be close to the mean, while a high standard deviation indicates that the values are spread out over a wider range. Understanding standard deviation is crucial for calculating the coefficient of variation and interpreting the spread of pulse rates in the given samples.
Recommended video:
Guided course
08:45
Calculating Standard Deviation

Mean

The mean, or average, is a measure of central tendency that is calculated by summing all the values in a dataset and dividing by the number of values. It provides a single value that represents the center of the data distribution. In the context of pulse rates, the mean pulse rate for each gender will be essential for calculating the coefficient of variation and comparing the overall pulse rates between males and females.
Recommended video:
Guided course
04:52
Calculating the Mean