# Author Archives: Alex Jeppson

## Hypothesis Test for Two Independent Means

When you want to find the difference of two means, you should use a hypothesis test for two independent means. You need two independent variables in this test. One must be categorical (i.e. men or women, employed or unemployed) and the other must be quantitative (i.e. temperature, salary). This test has five steps, which are […]

## Residual Plots

A residual plot is a graph used to demonstrate how the observed value differ from the point of best fit. A residual plot will have the appearance of a scatter plot, with the residuals on the y-axis and the independent variable on the x-axis. A residual plot is used to determine if residuals are equal, which is […]

## Frequency Tables

A frequency table lists each group of data and the number of occurrences for each category of data. The groups are usually categories (such as car color), intervals (as seen on the right), or values (like number of cars) that will be recorded in the first column. If the classes are numerical, then they need to be […]