Anova or Chi Square for checking significant related effects


I am a newbie to Data Analysis and would be thankful if you could explain to me if for this exercise I use Chi Square or Regression ( looking at the ANOVA table). For each what would be the specific steps? For example for Regression which is the dependent variable, etc.


You are given the number of defective lots per company and per month (in columns compA, compB and compC). You would like to check if there is a significant month related effect.

1) Which test is relevant here? Why?

2) Can we say that there is a significant monthly related effect?

3) On the same moth, you are given data before and after an inspection in the plant. You will find the relevant data below. Can we say that the inspection significantly changed the results? Do not forget to give the 95% confidence interval.

Thanks a lot in advance!


Omega Contributor
Chi-sq used when you have categorical variables.

ANOVA used when you have categorical and continuous variables.

What do you have?

i have posted the data i have below in a picture.

Its about company A, B, C and their results in month January, February and March.
The data is presented in a table ( see picture above)

Comp A:

Jan: 15
Feb: 48
March: 25

Comp. B:

Jan: 5
Feb: 55
Mar: 2

Comp. C:

Jan: 1
Feb: 2
Mar: 3
I have to check if there is a significant month related effect.

Thank you!


Omega Contributor
I could see the data. I was asking you to define what type of data it was (categorical, continuous) . Any educated guesses?