Need Help With Case In Statistics

Hi there!

I'm attending a Norwegian business school, and we have just received a
case analysis which will in part be basis for the exam. There are no
restrictions concerning what sources of information we are allowed to
use, including other people (just so you know I'm not cheating).

I will be using SPSS, and I'm especially interested in which
statistical methods are the best to analyze the information given in
the case. The questions are kinda broad, so the wider the analysis,
the better.


Question 1: Kebab

Smp. 1
467 465 519 439 462 482 482 484 465 443 500 430 480 450 460 480 450
470
Smp. 2
524 553

The authorities wanted to control whether the shop had entered costs
based on a higher weight per kebab than was the actual case. The first
sample consisted of 18 kebabs bought during a single day. The second
consisted of two kebabs bought during another day.

a) Combine the samples and analyse the data. Is it reasonable to
assume a population mean (average) of 460 gram?

- In this question it seemed reasonable to use a One-Sample t-test
comparing means. The results were significant on the 5-percentile.

b) Is it reasonable to assume that the two samples are from the same
population? How does this illuminate the authorities' assessment
taxation?

- I'm a litte stuck here. Can Mann-Whitney's test be used when one of
the samples contain only 2 observations? Do we have necessary
information to run tests?



Question 2: Blonde test

Are blondes more stupid than brunettes? The test consists of five
questions, and 46 girls were given the test. We are not told how many
of the 46 that were blondes and brunettes. (The scores are in %)

b) Suppose there were 23 girls in each category. Is there a
significant difference between blondes and brunettes?

- I found it natural to run a Chi-Square test with a 2X5 matrix. The
results weren't significant.

c) Will another distribution of the 46 girls according to blondes and
brunettes change the conclusion from b)?

- I'm not quite sure how to test this. I found that changing the
distribution changed the results to a certain point, but never enough
to be significant.



Question 3: Do stock brokers deserve their commission?

The table (http://home.bi.no/fag87027/met8006/var07/
megleranbefalinger.xls) shows the relationship between the number of
times a share at Oslo Stock Exchange (OSE) has been recommended during
2006, and the rise in the share's price during the year. There are a
total of 60 shares listed in the tables, half of them with 12
recommendations or more.

a) Analyse the relationship using a fitting model from your
curriculum. Let x be the increase in price and y the number of
recommendations.

- I used simple regression, and found no correlations whatsoever. Any
numbers I should be on the lookout for?

b) The increase in the OSE index was 30,9 % for the period (up to
22/11). Compare this with the increase in price of the shares that
were recommended at least 12 times.

- This is the question that bothers me the most, because I have no
data on the OSE index besides the mean (and of course the 60 shares
which are part of it)! What could they possibly ask for here? Is there
a way to compare means using a t-Test with only this information?

That's it, I really hope you guys can help me out and through out as
much information as possible.

Here's the case in it's entirety: http://home.bi.no/fag87027/met8006/var07/exc23041_250507case.pdf

Thanks in advance!

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