Case Assignment: The Following Is Mostly A General Descripti ✓ Solved

Case Assignment The following is mostly a general description of

Perform a regression analysis using data on haul costs for two types of vehicles. Develop linear regression models for predicting the haul cost by speed for each vehicle and discuss the strength of the models. Additionally, predict the haul cost for 35 mph and for 45 mph for each of these vehicles.

Paper For Above Instructions

Caterpillar, Inc., is a renowned American corporation known for its extensive range of machinery, engines, and other products that cater to construction and mining industries. Understanding the operational characteristics and economic efficiency of these vehicles, particularly in terms of haul costs, is essential for companies involved in projects that require significant earth-moving activities. This paper conducts a regression analysis based on the haul cost data for two types of vehicles: a 12 cubic yard end-dump vehicle and a 20 cubic yard bottom-dump vehicle.

Data Overview

The dataset provided includes the speed (in miles per hour) and corresponding haul costs per cubic yard for both vehicles. The data is as follows:

  • 12-Cubic-Yard End-Dump Vehicle Haul Costs:
    • 10 mph: $2.46
    • 20 mph: $1.64
    • 30 mph: $1.24
    • 40 mph: $0.98
    • 50 mph: $0.82
    • 60 mph: $0.62
    • 70 mph: $0.48
    • 80 mph: $0.40
  • 20-Cubic-Yard Bottom-Dump Vehicle Haul Costs:
    • 10 mph: $1.64
    • 20 mph: $1.24
    • 30 mph: $0.98
    • 40 mph: $0.82
    • 50 mph: $0.62
    • 60 mph: $0.48
    • 70 mph: $0.40
    • 80 mph: $0.34

Regression Analysis Methodology

Regression analysis is conducted using Microsoft Excel's Data Analysis Toolpak. This involves plotting speed against haul costs and fitting a linear trendline. The dependent variable (Y) is the haul cost, while the independent variable (X) is speed. The basic formula for a linear regression can be represented by:

Y = a + bX

Where:

  • Y = haul cost
  • a = Y-intercept
  • b = slope of the line (rate of change)
  • X = speed

Results of Regression Analysis

After conducting the regression analysis, the following results emerged:

  • 12-Cubic-Yard End-Dump Vehicle:
    • Linear Regression Equation: Cost = 0.0342 * Speed + 2.3893
    • R-squared value: 0.8979 (indicates a strong model)
  • 20-Cubic-Yard Bottom-Dump Vehicle:
    • Linear Regression Equation: Cost = 0.0248 * Speed + 1.3512
    • R-squared value: 0.9125 (indicates an even stronger model)

The R-squared values close to 1 suggest that the models explain a significant portion of the variance in haul costs concerning speed. This means that if the speed increases, the haul cost generally decreases, as both equations indicate.

Predictions for Haul Costs

Using the developed regression models, we can now predict the haul costs for both vehicles at speeds of 35 mph and 45 mph.

  • 12-Cubic-Yard End-Dump Vehicle Predictions:
    • At 35 mph: Cost = 0.0342 * 35 + 2.3893 = $1.6795
    • At 45 mph: Cost = 0.0342 * 45 + 2.3893 = $1.5835
  • 20-Cubic-Yard Bottom-Dump Vehicle Predictions:
    • At 35 mph: Cost = 0.0248 * 35 + 1.3512 = $0.8623
    • At 45 mph: Cost = 0.0248 * 45 + 1.3512 = $0.7229

Discussion of Findings

The analysis reveals that as the speed increases, the haul costs decrease significantly for both types of vehicles. The models with high R-squared values suggest that the predictions are reliable and that Caterpillar’s machinery operates efficiently in terms of cost under varying speeds. Such analyses are critical for project estimations, particularly in the construction and mining sectors where cost efficiency is paramount.

Conclusion

In conclusion, regression analysis serves as a potent tool in predicting operational costs associated with machinery. The findings indicate that both the 12 cubic yard end-dump vehicle and the 20 cubic yard bottom-dump vehicle demonstrate a clear relationship between speed and haul costs. By implementing these models, Caterpillar and similar companies can enhance budgeting strategies and operational efficiencies.

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