I just bought an Abarth 124 Spider!

With only a few months left on my current finance agreement, I decided to release some positive equity in my current vehicle and get something new. I decided I wanted to go down the roadster route, and after test driving the MX5 and the Abarth 124, I’ve decided on the latter. The dealership let me have the car all of today, and I fell in love with it – the record monza exhaust sounds incredible. I even I take delivery at the end of the month, I shall post some pictures then! Very excited indeed!

submitted by Nevin Manimala Nevin Manimala /u/adamhilditch
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Simple Questions – June 08, 2018

This recurring thread will be for questions that might not warrant their own thread. We would like to see more conceptual-based questions posted in this thread, rather than “what is the answer to this problem?”. For example, here are some kinds of questions that we’d like to see in this thread:

  • Can someone explain the concept of maпifolds to me?

  • What are the applications of Represeпtation Theory?

  • What’s a good starter book for Numerical Aпalysis?

  • What can I do to prepare for college/grad school/getting a job?

Including a brief description of your mathematical background and the context for your question can help others give you an appropriate answer.

submitted by Nevin Manimala Nevin Manimala /u/AutoModerator
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Arch_model in Python returning nonsense residuals

Has anyone noticed this problem where the residuals are identical to the original data plus a (nonzero) constant?

np.random.seed(2)

a0 = 0.2

a1 = 0.5

b1 = 0.3

n = 10000

w = np.random.normal(size=n)

eps = np.zeros_like(w)

sigsq = np.zeros_like(w)

for i in range(1, n):

sigsq[i] = a0 + a1*(eps[i-1]**2) + b1*sigsq[i-1]

eps[i] = w[i] * np.sqrt(sigsq[i])

res = arch_model(eps).fit(update_freq=5)

eps – res.resid # This returns a constant vector

I ask because I noticed some obscure errors when installing Cython which is a prereq to the arch package. Thanks a lot.

submitted by Nevin Manimala Nevin Manimala /u/nearly-human
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