/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 13 How does the speed of a runner v... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

How does the speed of a runner vary over the course of a marathon (a distance of \(42.195 \mathrm{~km}\) )? Consider determining both the time to run the first \(5 \mathrm{~km}\) and the time to run between the \(35-\mathrm{km}\) and \(40-\mathrm{km}\) points, and then subtracting the former time from the latter time. A positive value of this difference corresponds to a runner slowing down toward the end of the race. The accompanying histogram is based on times of runners who participated in several different Japanese marathons ("Factors Affecting Runners' Marathon Performance," Chance, Fall, 1993: 24-30). What are some interesting features of this histogram? What is a typical difference value? Roughly what proportion of the runners ran the late distance more quickly than the early distance?

Short Answer

Expert verified
The histogram's peak shows a typical positive difference, indicating slower times in the late segment. A minority of runners have negative differences, meaning they ran the late segment faster.

Step by step solution

01

Understand the Problem

We need to calculate the difference in time it takes runners to complete two segments of a marathon: the first 5 km and the portion between 35 km and 40 km. A positive difference indicates slower running later in the race.
02

Analyze Histogram Data

Examine the histogram to see how the difference in time (for the early segment minus the late segment) is distributed. Identify the peak of distribution to determine the typical difference value.
03

Identify Typical Difference Value

Review which time difference interval contains the largest number of runners. This interval represents the typical difference value of time taken between the early and late segments.
04

Calculate Proportion of Faster Runners

Find the histogram area corresponding to negative time differences (where early segment times are greater than late segment times), indicating runners who were faster in the later segment. Calculate what proportion of the total this represents.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Marathon Performance Analysis
Marathon performance analysis involves examining how runners complete a marathon's challenging 42.195 km distance. A key aspect of this analysis is comparing different segments of the race to understand variations in a runner's speed. By examining the time taken to run the first 5 km and the time spent on the 35 km to 40 km stretch, we can determine whether there's a notable change in pace. If a runner takes longer in the latter segment, it suggests fatigue or difficulty in maintaining speed.
  • This analysis can help in identifying patterns related to endurance and pacing strategies.
  • Understanding these variations can aid runners in tuning their training programs for better performance in future events.
  • It provides insights into how external factors, like weather or terrain, might influence performance.
Recognizing patterns in marathon performance is crucial for optimizing strategies and enhancing overall endurance.
Histogram Interpretation
Interpreting a histogram involves understanding the distribution of data points across different intervals or bins. In the context of our marathon performance data, the histogram shows how the time differences between two segments of the race are distributed among runners.
  • The x-axis represents the time difference: positive values show a slowdown in the later segment, while negative values indicate a speed-up.
  • The y-axis shows the number of runners in each time difference interval.
  • The peak of the histogram, or mode, shows the most common time difference, indicating the typical performance trend.
This interpretation helps in identifying the typical pace change among marathoners and in assessing overall performance trends.
Statistical Problem Solving
Statistical problem solving uses data analysis methods to address complex questions like those found in marathon performance assessments. By using histograms and other statistical tools, we can systematically break down data to identify trends and patterns. This approach allows us to:
  • Quantify performance changes over different marathon stages.
  • Assess the impact of training regimens or environmental conditions.
  • Draw insights from observable data trends to help runners improve their strategies.
By applying statistical methodologies, we can obtain a clearer, data-driven view of marathon running dynamics, helping in theory development and practical training advice.
Runner Speed Variation
Runner speed variation explores how individual speeds fluctuate throughout a marathon. Understanding this variation is key for runners and coaches who aim to optimize race strategies.
  • A positive time difference suggests a runner slows down in the race's latter stages, perhaps due to fatigue or suboptimal pacing.
  • A negative time difference may imply efficient energy management or an acceleration strategy near the race's end.
  • By recognizing these speed variations, training can be adjusted to emphasize endurance and strong finishing sprints.
Analyzing speed variation helps in crafting personalized training plans that cater to a runner's strengths and weaknesses, ultimately leading to improved marathon performance.

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Most popular questions from this chapter

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