March, 14, 2017

Two Group Comparisons

  • Midterm is on March 21st

  • Topics will include everything covered from the beginning of the semester to this past Tuesday (03-14)

The Basics

  • Populations and samples.

  • Parameters and statistics.

  • Variables and their measurement- quantitative/qualitiative, discrete/continuous.

  • Randomization - causal inference,statistical sampling (with/without replacement).

  • Observational studies, experiments and bias - sampling error, bias.

  • Bias - sampling bias, response bias, nonresponse bias.

Visualization and summarization

  • Bar plots.

  • Histograms.

  • Descriptive statistics - mean, median, mode.

Measures of spread

  • Standard deviation.

  • Range.

  • Quartiles, quantiles, outliers.

Probability and probability distributions

  • Difference between Bayesian and frequentist probability.

  • Probability rules - compliments, unions, intersections.

  • Discrete and continuous distributions.

  • Distribution shapes - left, right, symmetrical.

  • The empirical rule.

The Normal Distribution

  • Properties.

  • Parameters and how they effect the normal distribution.

  • The standard normal distribution and its properties - z-values.

Sampling distributions

  • What is a sampling distribution?

  • Standard error of sampling distribution.

Confidence intervals

  • Constructing confidence intervals for any given confidence level.

  • Interpreting confidence intervals.

Significance tests

  • Conducting significance tests.

  • Significance tests for one sample.

  • Significance tests for two independent samples.

Type I and Type II Errors

  • Identifying Type I and Type II errors.

  • Definitions.