Estimation

INFO

Techniques that allows analysts to approximate population parameters using sample data while accounting for uncertainty

  • point estimation
  • confidence intervals
    • provide range of plausible values for a parameter
    • offer insights into the reliability of an estimate
  • Common Employed Methods
    • Maximum Likelihood Estimation (MLE): focus on finding the parameter values that maximize the probability of observed data
    • Bayesian estimation: incorporates prior knowledge to update beliefs based on new evidence

Hypothesis Testing

INFO

enables data scientists to assess the validity of claims or assumptions about population characteristics

  • formulates null and alternative hypothesis
    • uses statistical tests to determine whether observed patterns are due to chance or reflect significant underlying relationships
      • t-test
      • chi-square test
      • ANOVA
      • correlation
      • regression-based tests
    • selection of appropriate test depends on factors
      • sample size
      • distribution assumptions
      • nature of variables under investigation
    • p-values and confidence intervals helps quantify the strength of evidence against the null hypothesis, guiding decision-making
  • Essential to account for potential errors, which can influence the reliability of inferences
    • Type I (false positives)
    • Type II (false negatives)
  • Hypothesis

INFO

  • testable statement about the relationship between 2 or more variables or a proposed explanation for some observed phenomenon
  • brief summation of the researcher’s prediction of the study’s findings, which may or may not be supported by the outcome

IMPORTANT

Core of scientific method

  • statistical hypothesis

INFO

method of statistical inference used to decide whether the data at hand sufficiently support a particular hypothesis

  • In business analytics
    • provides a structured framework for evaluating whether observed data significantly deviate from established norms or expectations → guiding strategic decisions
  • In marketing
    • helps to determine if changes in strategy lead to significant differences in consumer behavior to identify variations in manufacturing processes and assess their impact on product quality
  • Approaches to Hypothesis Testing
    • modern statistical inference techniques
      • leveraged computational advancements
        • enhance accuracy and scalability
    • Resampling methods
      • bootstrapping and permutation testing
      • provide robust alternatives when parametric assumptions are difficult to meet
    • Bayesian inference
      • gained prominence in machine learning applications
        • probabilistic modeling and reinforcement learning
    • Integration of statistical inference with artificial intelligence techniques enables more sophisticated analyses
      • Monte Carlo methods
      • Markov Chain Monte Carlo (MCMC) simulations
    • Allowed to
      • quantify uncertainty
      • make probabilistic predictions
      • refine models dynamically based on new data
      • reinforcing the critical role of statistical inference in driving data-driven decision-making