（对不起，帖子不知道该在哪里发）在大学必修的科目之一是Introduction to Statistics，不及格就不能毕业。但是本人对理科一窍不通。有没有好心的同学们帮帮忙，应该是一些基础问题。
A certain psychologist wanted to look at the relation between “selfishness” and “being offended”
and find the regression equation. First he created two different tests to quantify the amount
selfishness (X) and the amount of being offended (Y). His goal was building a linear regression
model to predict the amount of being offended based on the quantification of selfishness. For the
dependent variable he found an average of 51.8 with a variance of 856.2 and for the independent
variable he found respectively 32 and 407.5. The correlation between the two variables was positive
with a value of 0.4262. He wanted to find the values for the regression coefficients and write out the
equation in the following form:
Yi=b0b1 X i
Find the values for b0 and b1 (intercept and slope).
4
Question 10 (15 points)
In some earlier research the same psychologist studied the relation between some one's selfishness
and the total length of a romantic relation with his or her partner. To do this he asked the
respondents how selfish they were (X) and how long their previous relation had last (Y). He found a
negative relation between the two measures with the following regression equation:
Yi=56−0.25Xi
His girlfriend just broke up with him after exactly 11 years of romance and happiness but
unfortunately also a lot of selfishness from her side (she always helped herself to his piece of cake).
Since he was still able to get an hold on her selfishness-score X =165 , he wanted to see
whether the break up after 11 years was actually early or not (according to the model).
Find the predicted value according to the model and give the residual for the length of their relation
egirlfriend and state whether this actual break up was rather early or late.
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