Statistics How To

Probability and Statistics > Basic Statistics > Pooled Sample Standard Error Pooled Sample Standard Error: Overview The standard error of a sample is another name for the standard deviation of a sample (this is also one of the AP Statistics formulas). There’s a slight difference between standard deviation and pooled sample standard error: When we … Read more

Binomial Theorem > Success/Failure Condition What is the Success/Failure Condition? Sometimes with a binomial experiment, we can use a normal distribution to approximate a binomial; This can make finding probabilities easier for some experiments—especially when you’re dealing with large samples. The Success/Failure condition is used to figure out if a sample size in a binomial … Read more

Hypothesis Testing > Two-Sample T-Test What is a Two-Sample T-Test? A two-sample t-test is used when you want to compare two independent groups to see if their means are different. When to use a Two-Sample T-Test vs. a Paired T Test “Independent” implies that the two samples must have come from two completely different populations. … Read more

Statistics Definitions > What is a Dot Plot Dot Plot: Definition A Dot Plot, also called a dot chart or strip plot, is a type of simple histogram-like chart used in statistics for relatively small data sets where values fall into a number of discrete bins (categories). A dot plot is similar to a bar … Read more

Statistics Definitions > Direction of Association Direction of Association: Overview In Statistics, association tells you whether two variables are related. The direction of the association is always symbolized by a sign either positive (+) or negative (-). There are two directions of association: positive association and negative association. Positive association is also the same as … Read more

Statistics Definitions > What is a Segmented Bar Chart? Segmented Bar charts are one of the most popular charts used in Statistics. They are a type of stacked bar chart. In order to understand this chart, first you’ll need to understand the idea of bar charts and stacked bar charts . Bar graphs represent comparisons … Read more

Statistics Definitions > Lowess Smoothing Lowess Smoothing: Overview LOWESS (Locally Weighted Scatterplot Smoothing), sometimes called LOESS (locally weighted smoothing), is a popular tool used in regression analysis that creates a smooth line through a timeplot or scatter plot to help you to see relationship between variables and foresee trends. What is Lowess Smoothing used for? … Read more

Mean > Find the Mean in Minitab How to Find the Mean in Minitab The mean is the average number of a dataset. To find an average, you sum all of the numbers and then divide by the number of items in the data set. For example, the average (mean) of the set 3, 2, … Read more

Statistics Definitions > T Statistic What is a T Statistic? The T Statistic is used in a T test when you are deciding if you should support or reject the null hypothesis. It’s very similar to a Z-score and you use it in the same way: find a cut off point, find your t score, … Read more