About this Video

• Video Title: Diseño de experimentos un factor con excel
• Channel: Herramientas ingeniería
• Speakers: Andreu Ayala
• Duration: 00:16:34

Introduction

This video demonstrates how to perform a one-factor experiment design using Microsoft Excel. The presenter, Andreu Ayala, explains experimental concepts, statistical distributions (normal, t, chi-squared, and F), and applies these to analyze data from a footwear manufacturer's experiment comparing four types of shoe leather.

Key Takeaways

• Defining Experiments: An experiment involves changing operational conditions to measure the effect on product properties. This requires experimental units (samples) to generate values representing the results.
• Variables, Factors, and Levels: Variables are values resulting from experimental unit and factor interactions. Factors are controllable conditions (e.g., temperature, humidity), and levels are their values (e.g., 20°C and 60°C for temperature). Fewer levels are recommended for easier analysis.
• Statistical Distributions: The video uses four key probability distributions: normal, t, chi-squared, and F. The first two relate to the mean, the last two to variance. The choice depends on sample size (normal and chi-squared for large samples; t and F for small).
• Analysis of Variance (ANOVA): ANOVA is used to determine if there's a significant difference between groups. The F-statistic is compared to a critical value; if calculated F exceeds the critical F, the null hypothesis (no difference) is rejected.
• Mintab Software: Minitab (version 19 in the video) is used to create interval plots for visualizing and interpreting the differences between leather types. Overlapping intervals indicate no significant difference, non-overlapping intervals suggest significant differences.

The transcript does not explicitly list formulas used. The video shows the application of ANOVA (Analysis of Variance) within Excel and Minitab, but the specific formulas used by these programs for calculations are not detailed in the spoken transcript. To obtain the formulas, you would need to consult the documentation for Excel's Data Analysis Toolpak (specifically, the ANOVA: Single Factor function) and Minitab's ANOVA procedures.