Looking for simple step-by-step explanations and solutions

1.  Samples of 5 families were randomly selected.  The amount of money
spent buying groceries were as follows:

X: 3  6  5  6  6
Y: 99 104 151 129 142

Compute the coefficient of correlation.
Calculate the OLS based standard error of residual and standard error
of estimate


2.  Following sample observations (6) were selected from population of
40.

X : 92  95  99  97  102  104
Y:  95  56  57  58  59  60

EXi = 589  EXi~2 = 57919  EYi = 345  EYi~2 = 19855  EXiYi = 33907

Draw scatter plot
What would be the direction of causation from X to Y, what would be
the functional linearity that will connect X and Y and how would you
express sample liner regression function and model.
Based on sample simple liner regression model with ordinary least
squares approach estimate the population simple linear regression
model.
What will be the interpretation of estimated slope coefficient?
Based on standard error of residual and estimate determine the OLS
For simple linear regression function slope parameter do a test of
significance level 1%.
What will be the 95% confidence interval for slope parameter of
population simple linear regression?


nada

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Request for Question Clarification by elmarto-ga on 21 Oct 2003 06:28 PDT

Hi nada16!
I'd like to answer your questions, but I would need some clarification
first.

- What do you mean by "what's the direction of causation from X to Y"?
I ask this because from the question it would appear that the
direction of causation is effectively from X to Y; otherwise the
question would be "what's the direction of causation?".

- There are also some statistics "EXi = 589  EXi~2 = 57919 ...". These
are clearly not referring to the sample (for example, the range of X
in the sample is from 92 to 104, so its mean could never be 589). What
are these statistics referring to?

Thanks a lot,
elmarto

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Clarification of Question by nada16-ga on 21 Oct 2003 16:03 PDT

Hi elmarto
clarifications are as follows

I have to nominate linearity as the functional form that connects X
and Y and the direction of causation is from X to Y
 
This statistics are part of the question I am not sure what it is
referring to
maybe it is there to confuse! 

regards
nada16