Business Analytics quiz 2

Chi-Squared Goodness of Fit

Compares observed and expected frequencies based on categorical data

Chi-squared test of Independence

determines if two categorical variables are related based on comparing observed and expected frequencies

Z test

Know the SD and sample size is greater than 30

One-sample T-test

Comparing sample mean to population mean. SD is unknown OR sample size is less than 30

Independent T-test

Comparing means of 2 independent groups. SD is unknown OR sample size is less than 30

Paired T-test

Comparing means of same group at 2 different times. SD is unkown OR sample size is less than 30

ANOVA

Comparing means across 3 or more groups

If T stat is negative

Lower tail

If T stat is positive

upper tail

Variance is equal to

SD²

Two tail / two sample

Looking for more than one result

Ex. Above or below

One tail / One sample

Looking for one result

Ex. Just above

Regression

Used to understand relationship between 2 things

Time series analysis

predictive analytics technique used to predict future values based on past values of the same variable

Base Rate

Probability of some event occurring based on some historical average

Base Rate Fallacy

when a prediction places too little weight on the base rates of the past and instead uses different or new information as the basis for the prediction

Parameter

A numerical summary that describes a population.

Statistic

A numerical summary that describes a sample.

Vertical analysis

Relative size within one period

Horizontal analysis

Change over time