# What data cleaning to do for logit regression with only dummies?

Does anyone know what exact data cleaning steps one need to undertake in order to clean data for a logit regression (not a logistic regression)?

I have only time variables, meaning year and month, as my independent variables, and I am using R.

A logit regression is simply a normal linear regression where the DV have been transformed with the following formula:

logit(y) = ln(y/(1-y) for

An example:

3 of 12 people gets cured from taking a pill in period 3 -> ln(0.25/(1-0.25)

5 of 25 people gets cured taking a pill in period 5 -> ln(0.20/(1-0.20)

One can use the logit transformation if you have ratios and in many papers and books it is closely related to the logistic regression.

• I don't know logit regression. Can you give more details?(especially because you say it is NOT logistic regression) – Momo Mar 9 '13 at 21:13
• Sorry. Question changed, with better explanation. – Kasper Christensen Mar 9 '13 at 21:50
• OK, I see. Although it won't help you directly with your problem, I don't think you should use this technique as the equal variance and mean and variance are independent assumptions are likely not met. An alternative might be to use a (quasi-)binomial model if you know the successes and trials or a Beta model if you have only proportions. – Momo Mar 9 '13 at 22:19