# When are OLS estimators BLUE?

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For Classical Regression Model the OLS or Ordinary Least Squares - estimators (or the betas) are BLUE (Best, Linear, Unbiased, Estimator) when :
1. The regression is linear in the coefficients, it is correctly specified and has an additive error term.
2. Mean of the error term is zero. (Include a constant term in the regression (B0 which will force the mean to be zero)
3. The independent variables are not correlated with the error term. (If they are correlated then the betas will be biased.)
4. Observations of the error term (the residuals) are not correlated with each other.
5. The error term has a constant variance (Homoskedasticity)
6. No independent variable is a perfect linear function of any of the other independent variable. (If this is true - multicollinearity will occur)
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frank Sinatra

# Who gave Frank Sinatra the nickname Ol' Blue Eyes?

Because his eyes are all messed up.

# How did frank Sinatra get his nickname Ol' blue eyes?

He titled his comeback album in 1973 "Ol' Blue Eyes is Back". The name stuck.

# Who is ol' blue eyes?

Frank Sinatra ---------------- See http://en.wikipedia.org/wiki/Frank_Sinatra

# Who is ol blue eyes?

Frank Sinatra ------------ See http://en.wikipedia.org/wiki/Frank_Sinatra

Frank Sinatra

Frank Sinatra

# In the presence of heteroscedasticity OLS estimators are biased as well as inefficient?

They are still unbiased however they are inefficient since the variances are no longer constant. They are no longer the "best" estimators as they do not have minimum variance

# Which singer is commonly reffered to as ''OL' blue eyes''?

Francis Albert Sinatra, a.k.a Frank Sinatra.

# Why is frank Sinatras nickname ole blue eyes?

Because he had beautiful blue eyes made even more striking by his black hair and tanned face.

# What is the estimation of Blue Whales?

A rough estimation is in low few thousands. This is because their were hunted and classed as endangered by 1950s. The pre-whaling population is estimated to be around 350,000

# Why was Stonewall Jackson also referred to as Ol' Blue Light?

ANSWER Because he was a bright blue eyed man with a bright glance.

Mansoor Ahmed

# When was Ol' Rag Blues created?

Ol' Rag Blues was created on 1983-09-02.
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# When was Ol' Blue Eyes Is Back created?

Ol' Blue Eyes Is Back was created on 1973-06-04.
In Eyes

# When was Ole Black 'n' Blue Eyes EP created?

Ole Black 'n' Blue Eyes EP was created in 2006.

# What are the release dates for Tornado Chasers - 2012 Ole Blue 1-4?

Tornado Chasers - 2012 Ole Blue 1-4 was released on: USA: 1 October 2012