Can a believer believe an unbeliever

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Can a believer believe an unbeliever?
http//www.imdb.com/title//

• Omar Sherif in Hidalgo (2004)

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Computer Science 101Lecture 9
www.pjrc.com/tech/ 8051/board5/schematic.gif

• Spring Semester 2008
• Wednesday, January 30
• Week 4/18
• Albert H. Carlson

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Announcements

• HW 2 is due on Friday, February 8
• First exam is coming up on February 8, as well.
  Get your HW done early. All HWs, with the
  exception of HW4 are up.

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Notation

• Notice that when I list ALL of the members of the
  solution space, I use the notation
• item0,item1,,itemn
• The indicate a set
• When I specify a range I use
• or , indicating the number is included
• ( or ), indicating the number is NOT included
  (ie, you can go right UP to that number)

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Statistics, Average

• One of the most common measures of data is the
  average
• The average is what you would expect to get if
  you randomly picked something from the solution
  set over and over again
• After you pick one, then replace it and record
  the answer and pick again
• Often show by the symbol µ

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How Do We Calculate the Mean

• Note that the solution set contains values drawn
  from the solution space, depending on how many
  times the experiment is conducted
• We calculate the mean by adding all of the
  members of the solution set and then dividing by
  the number of members in the set

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Calculating the Mean

• Where the xi represents each member of the
  solution set, n is the number of members of the
  set, and S means add all of the numbers together

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Example

• If we have the solution set 1,2,2,3,4,7,5
• n 7
• Then we add them all together
• Sxi 1223475
• Then, µ 24/7
• This means we would expect to get a 3 or a 4
  for each pick. We might not get it, but on the
  average we would

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3.42857
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Statistics, Median Value

• Median is a slightly different thing than a mean
• It is the middle number in a sorted list
• By sorted, we mean lowest to highest number, in
  order
• If the number of items in the list is odd, take
  the middle number
• If it is even, take the average of the two middle
  numbers

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Median Examples

• Given the list 23,6,8,9,1
• 1. Sort the list in ascending order. We get
• 1,6,8,9,23
• 2. Choose the middle value (this is an odd
  number of list members). The median is 8
• Add a 16 to the list. The new list is
• 1,6,8,9,16,23
• In this case the number of elements is even

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Median Example

• We have to find the two middle values in the
  sorted list
• These values are 8 and 9
• What we need to do is take the average of these
  two numbers
• The average is 17/2 8.5

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Variance

• Variance is a measure of how close the data is
  to the mean
• It is denoted by the symbol s2
• A high variance means that the data is spread
  out, a low variance means that the data is
  typically very close to the mean

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Statistics, Standard Deviation

• Another measure of dispersion
• The most commonly used measure
• Often used in research, so you should get to know
  it.

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Standard Deviation Example

• Let us work on the following sample set
• 1,2,3,4,5,6
• The mean is 21/6 3.5
• Now, lets do the s2
• s21/6((1-3.5)2(2-3.5)2(3-3.5)2
• (4-3.5)2(4-3.5)2(5-3.5)2(6-3.5)2)
• 1/6(6.252.25.25.252.256.25)
• 1/6(17.5) 2.91666

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Use of Statistics

• The statistics we have learned will be used in
  future assignments
• Keep this in your mind and know how to do it
• From the last example, s22.9166, therefore

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The Hardware/Software Test

• Hold up a Finger
• Try to touch the item of interest
• If your finger does NOT go through it, it is
  hardware
• Otherwise, it is software

http//fromcairo.blogspot.com/2005_09_01_fromcairo
_archive.html
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Hardware

• The Finger test for hardware or software
• Hardware components
• The chip
• Inductors (dangerous)
• Capacitors (dangerous)
• Memory (SIPS)
• Expansion cards

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Questions?