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	<title>Comments on: Notes on Representation &#8211; Tally Marks</title>
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	<description>math as a garden, friendly and always new</description>
	<lastBuildDate>Tue, 20 Dec 2011 20:42:50 +0000</lastBuildDate>
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		<title>By: Bert Speelpenning</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-699</link>
		<dc:creator><![CDATA[Bert Speelpenning]]></dc:creator>
		<pubDate>Tue, 20 Dec 2011 20:42:50 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-699</guid>
		<description><![CDATA[When it comes to how to get ideas integrated into a school system, that&#039;s the 64million dollar question.  I don&#039;t have any particular track record in this.
Depending on one&#039;s preference, one can start with interesting an individual teacher, or an individual textbook publisher, or somebody who puts on professional development for teachers.
For any of these to get very far, you are going to have to get specific.  In which grade would this be introduced, and what is the sequence of instruction, exercises, etc. that are designed to get to the understanding and the skill.  Addition, subtraction, multiplication and division are not usually taught all at the same time, so how would the Funforms stuff be interwoven with all the stuff that&#039;s currently in the various curricula - specifically, how would you interweave the binary stuff with decimal stuff?
Even though any specific proposal you make will still have to be adjusted and completely reworked once somebody expresses a cautious interest, without such a specific proposal, you may find that people will have trouble in making the translation from what you have sketched to some set of actions for them to take in their classrooms.
I mentioned professional development for teachers because it occurs to me that the first people who would have to really understand the binary system are the teachers themselves, and finding a way to have them learn and understand the intricacies of a number system is not a trivial thing.]]></description>
		<content:encoded><![CDATA[<p>When it comes to how to get ideas integrated into a school system, that&#8217;s the 64million dollar question.  I don&#8217;t have any particular track record in this.<br />
Depending on one&#8217;s preference, one can start with interesting an individual teacher, or an individual textbook publisher, or somebody who puts on professional development for teachers.<br />
For any of these to get very far, you are going to have to get specific.  In which grade would this be introduced, and what is the sequence of instruction, exercises, etc. that are designed to get to the understanding and the skill.  Addition, subtraction, multiplication and division are not usually taught all at the same time, so how would the Funforms stuff be interwoven with all the stuff that&#8217;s currently in the various curricula &#8211; specifically, how would you interweave the binary stuff with decimal stuff?<br />
Even though any specific proposal you make will still have to be adjusted and completely reworked once somebody expresses a cautious interest, without such a specific proposal, you may find that people will have trouble in making the translation from what you have sketched to some set of actions for them to take in their classrooms.<br />
I mentioned professional development for teachers because it occurs to me that the first people who would have to really understand the binary system are the teachers themselves, and finding a way to have them learn and understand the intricacies of a number system is not a trivial thing.</p>
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		<title>By: joelssteinberg</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-698</link>
		<dc:creator><![CDATA[joelssteinberg]]></dc:creator>
		<pubDate>Tue, 20 Dec 2011 13:18:14 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-698</guid>
		<description><![CDATA[another important  advantage to use of FUNFORMS is the ease and transparency with which operations take place and how seeing that happen reflects on the understanding of the same operations in the decimal system. I called that the second language effect.]]></description>
		<content:encoded><![CDATA[<p>another important  advantage to use of FUNFORMS is the ease and transparency with which operations take place and how seeing that happen reflects on the understanding of the same operations in the decimal system. I called that the second language effect.</p>
]]></content:encoded>
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		<title>By: joelssteinberg</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-696</link>
		<dc:creator><![CDATA[joelssteinberg]]></dc:creator>
		<pubDate>Sun, 18 Dec 2011 11:04:11 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-696</guid>
		<description><![CDATA[WOW! Thank you so much for looking and for commenting. You are correct about using FF as an octal or hexadecimal [or 32 or 64 bit] unit. We always figured we could demonstrate that by some sort of link across the top of two or three or more staffs. For even larger numbers, there is no reason not use a FF exponent. So that way E (7) to the E power would be 7 to the seventh power. If that does not get you to large enough numbers, you could have exponents of exponents or at least mutiples of exponents.

We were not so interested in very large numbers, but in helping people see operations from this very simple, totally mechanical viewpoint. This gives the learner a second language to look back at what s/he had to learn by rote before the possibility of critical thinking was available. [I have learned alot aabout what I already &quot;knew&quot;.]

Also we don&#039;t use zero as a number. Zero is an empty staff or an empty position, a much more representational feature, I believe.

I want to introduce FF into schools [and study what effects, if any,]. I think there are people with dyscalcuia who might be able to understand FF and then, maybe, move forward into our more complicated decimal numeral system.  One of my kids at his age 15 had a Eureka moment with fractions and said to me, &quot;Oh! That&#039;s why half of 1/4 is 1/8.&quot; 
I said, &quot;You didn&#039;t know that???!!!&quot; 
He said, &quot;Oh yes, I did know that, I just didn&#039;t know WHY.&quot;
So he got an insight that had previously been unavailable to him. {And he is a bright fellow.]

I look forward to further correspondence with you and some good ideas about how to move forward.

js]]></description>
		<content:encoded><![CDATA[<p>WOW! Thank you so much for looking and for commenting. You are correct about using FF as an octal or hexadecimal [or 32 or 64 bit] unit. We always figured we could demonstrate that by some sort of link across the top of two or three or more staffs. For even larger numbers, there is no reason not use a FF exponent. So that way E (7) to the E power would be 7 to the seventh power. If that does not get you to large enough numbers, you could have exponents of exponents or at least mutiples of exponents.</p>
<p>We were not so interested in very large numbers, but in helping people see operations from this very simple, totally mechanical viewpoint. This gives the learner a second language to look back at what s/he had to learn by rote before the possibility of critical thinking was available. [I have learned alot aabout what I already "knew".]</p>
<p>Also we don&#8217;t use zero as a number. Zero is an empty staff or an empty position, a much more representational feature, I believe.</p>
<p>I want to introduce FF into schools [and study what effects, if any,]. I think there are people with dyscalcuia who might be able to understand FF and then, maybe, move forward into our more complicated decimal numeral system.  One of my kids at his age 15 had a Eureka moment with fractions and said to me, &#8220;Oh! That&#8217;s why half of 1/4 is 1/8.&#8221;<br />
I said, &#8220;You didn&#8217;t know that???!!!&#8221;<br />
He said, &#8220;Oh yes, I did know that, I just didn&#8217;t know WHY.&#8221;<br />
So he got an insight that had previously been unavailable to him. {And he is a bright fellow.]</p>
<p>I look forward to further correspondence with you and some good ideas about how to move forward.</p>
<p>js</p>
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		<title>By: Bert Speelpenning</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-695</link>
		<dc:creator><![CDATA[Bert Speelpenning]]></dc:creator>
		<pubDate>Sun, 18 Dec 2011 03:49:21 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-695</guid>
		<description><![CDATA[Joel,
There is a long history in mathematics for people in different professions making strong contributions.  One of the most famous is Pierre de Fermat, who was a busy attorney, for whom mathematics was merely a hobby.

From looking at your presentation, I see essentially two things there:
1. a very thorough treatment of arithmetic in the binary number system, covering addition, subtraction, multiplication and division - both for whole numbers and for what you call fractions but which I&#039;ll call binary terminating fractions.
2. a pictorial representation of the binary numbers, involving flags on a staff.  The characteristics of the staff representation are that positions are equally spaced and that each position has either zero or one flag on the right, though on a temporary basis, staff positions can have multiple flags on the right or they can have flags on the left indicating negative values.  One of the positions on the staff is associated with the unity position and all other positions have double the value of the position above and half the value of the position below.  In this pictorial representation, &quot;F&quot; represents the value 3, assuming the unity value is at the top, and assuming that the lowest horizontal bar of the &quot;F&quot; is exactly one position below the top one.  &quot;L&quot; would represent the value 4, and &quot;E&quot; would represent the value 7, making these same assumptions.

What the pictorial representation allows you to do is to imagine arithmetic operations as a series of simple actions on the flags.  No addition tables or multiplication tables are needed, just some simple recipes as to what to do with a temporary situation of two flags in a single flag position.

What I&#039;m curious about is how you would mark the unity value in your system, and how you would deal with very large numbers.  A pictorial representation of 2^10+1 and 2^11+1 would look almost exactly the same.  In the much maligned system of Roman numerals, one hundred and one (CI) looks very different from one thousand and one (MI).  In our normal decimal system, 10001 looks somewhat different from 100001, though 1000000001 doesn&#039;t stand out as different from 10000000001.  At the very least, though, in our decimal system the numbers that we are likely to encounter in our daily lives all look quite distinct.  For numbers outside that range, we use something called scientific notation, which on a calculator may show up as 3.4E8.  This is intended to mean that the number isn&#039;t really 3.4, but what you get if you move the decimal point to the right 8 places, hence 340000000.
In a binary system you can do the same thing with a special notation that indicates that the unity position is some number of places above or below the unit position shown.

In the context of computer science, people often represent large binary numbers by breaking the binary number up in groups of 4.  Instead of writing 100100111000, you would break it up s 1001 0011 1000 and write each of these as a &quot;hexadecimal digit&quot;, here 934. The translation between binary notation and hexadecimal notation is so straightforward that you can think of the hexadecimal notation as a shorthand for the binary notation rather than a separate system with radix 16.

Since there are 16 hexadecimal digits, and normal digits only carry us from 0 to 9, we need six more, and traditionally the letters a,b,c,d,e, and f are used for that.  So fa8 is shorthand for 1111 1010 1000 or 111110101000.  As an alternative, I&#039;ve seen a system of flags before, but different from your scheme in that ones are marked with a flag on the right and zeroes are marked with a flag on the left.  What people quote as an advantage of that scheme is that you can be sloppy in writing it, not needing lined paper to pull it off.  Instead, you are using the flags on the left to mean negative values.

Your use of the flags on the left for negative values allows for number representations other than the ones you describe.  Instead of writing 15 as four flags on the right, you could represent it as 16-1, with one flag on the right (16) and one flag on the left (-1).  Implicit in your representation is that flags are either all on the left or all on the right, and any other situation is what you call &#039;temporary&#039;, just like having two flags in one position is something you only allow during operations.

Thank you for an interesting take on the binary number system.]]></description>
		<content:encoded><![CDATA[<p>Joel,<br />
There is a long history in mathematics for people in different professions making strong contributions.  One of the most famous is Pierre de Fermat, who was a busy attorney, for whom mathematics was merely a hobby.</p>
<p>From looking at your presentation, I see essentially two things there:<br />
1. a very thorough treatment of arithmetic in the binary number system, covering addition, subtraction, multiplication and division &#8211; both for whole numbers and for what you call fractions but which I&#8217;ll call binary terminating fractions.<br />
2. a pictorial representation of the binary numbers, involving flags on a staff.  The characteristics of the staff representation are that positions are equally spaced and that each position has either zero or one flag on the right, though on a temporary basis, staff positions can have multiple flags on the right or they can have flags on the left indicating negative values.  One of the positions on the staff is associated with the unity position and all other positions have double the value of the position above and half the value of the position below.  In this pictorial representation, &#8220;F&#8221; represents the value 3, assuming the unity value is at the top, and assuming that the lowest horizontal bar of the &#8220;F&#8221; is exactly one position below the top one.  &#8220;L&#8221; would represent the value 4, and &#8220;E&#8221; would represent the value 7, making these same assumptions.</p>
<p>What the pictorial representation allows you to do is to imagine arithmetic operations as a series of simple actions on the flags.  No addition tables or multiplication tables are needed, just some simple recipes as to what to do with a temporary situation of two flags in a single flag position.</p>
<p>What I&#8217;m curious about is how you would mark the unity value in your system, and how you would deal with very large numbers.  A pictorial representation of 2^10+1 and 2^11+1 would look almost exactly the same.  In the much maligned system of Roman numerals, one hundred and one (CI) looks very different from one thousand and one (MI).  In our normal decimal system, 10001 looks somewhat different from 100001, though 1000000001 doesn&#8217;t stand out as different from 10000000001.  At the very least, though, in our decimal system the numbers that we are likely to encounter in our daily lives all look quite distinct.  For numbers outside that range, we use something called scientific notation, which on a calculator may show up as 3.4E8.  This is intended to mean that the number isn&#8217;t really 3.4, but what you get if you move the decimal point to the right 8 places, hence 340000000.<br />
In a binary system you can do the same thing with a special notation that indicates that the unity position is some number of places above or below the unit position shown.</p>
<p>In the context of computer science, people often represent large binary numbers by breaking the binary number up in groups of 4.  Instead of writing 100100111000, you would break it up s 1001 0011 1000 and write each of these as a &#8220;hexadecimal digit&#8221;, here 934. The translation between binary notation and hexadecimal notation is so straightforward that you can think of the hexadecimal notation as a shorthand for the binary notation rather than a separate system with radix 16.</p>
<p>Since there are 16 hexadecimal digits, and normal digits only carry us from 0 to 9, we need six more, and traditionally the letters a,b,c,d,e, and f are used for that.  So fa8 is shorthand for 1111 1010 1000 or 111110101000.  As an alternative, I&#8217;ve seen a system of flags before, but different from your scheme in that ones are marked with a flag on the right and zeroes are marked with a flag on the left.  What people quote as an advantage of that scheme is that you can be sloppy in writing it, not needing lined paper to pull it off.  Instead, you are using the flags on the left to mean negative values.</p>
<p>Your use of the flags on the left for negative values allows for number representations other than the ones you describe.  Instead of writing 15 as four flags on the right, you could represent it as 16-1, with one flag on the right (16) and one flag on the left (-1).  Implicit in your representation is that flags are either all on the left or all on the right, and any other situation is what you call &#8216;temporary&#8217;, just like having two flags in one position is something you only allow during operations.</p>
<p>Thank you for an interesting take on the binary number system.</p>
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		<title>By: Joel Steinberg</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-694</link>
		<dc:creator><![CDATA[Joel Steinberg]]></dc:creator>
		<pubDate>Sat, 17 Dec 2011 21:05:18 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-694</guid>
		<description><![CDATA[I hope you will have a look at Funforms, a tally mark, place order, binary number system. You can see and listen to a narrated power point presentation at:
http://www.authorstream.com/Presentation/joxl-1251628-funforms/]]></description>
		<content:encoded><![CDATA[<p>I hope you will have a look at Funforms, a tally mark, place order, binary number system. You can see and listen to a narrated power point presentation at:<br />
<a href="http://www.authorstream.com/Presentation/joxl-1251628-funforms/" rel="nofollow">http://www.authorstream.com/Presentation/joxl-1251628-funforms/</a></p>
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		<title>By: Tally Marks and Roman Numerals &#171; Learning and Unlearning Math</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-129</link>
		<dc:creator><![CDATA[Tally Marks and Roman Numerals &#171; Learning and Unlearning Math]]></dc:creator>
		<pubDate>Sun, 03 May 2009 23:46:47 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-129</guid>
		<description><![CDATA[[...] extending patterns, models, representations, unlearning by Bert Speelpenning   In earlier posts on tally marks, I mentioned that one of the drawbacks of tally marks as a representation system for [...]]]></description>
		<content:encoded><![CDATA[<p>[...] extending patterns, models, representations, unlearning by Bert Speelpenning   In earlier posts on tally marks, I mentioned that one of the drawbacks of tally marks as a representation system for [...]</p>
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		<title>By: Notes on Representation - Copying &#171; Learning and Unlearning Math</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-70</link>
		<dc:creator><![CDATA[Notes on Representation - Copying &#171; Learning and Unlearning Math]]></dc:creator>
		<pubDate>Sat, 07 Mar 2009 05:16:28 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-70</guid>
		<description><![CDATA[[...] representation systems for quantities, including the decimal number system, the number line, tally marks, and prime bags, and I&#8217;ve tried to see and say something interesting and fresh about each.  [...]]]></description>
		<content:encoded><![CDATA[<p>[...] representation systems for quantities, including the decimal number system, the number line, tally marks, and prime bags, and I&#8217;ve tried to see and say something interesting and fresh about each.  [...]</p>
]]></content:encoded>
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		<title>By: Notes on Representation - Tally Marks, Tully Marks &#171; Learning and Unlearning Math</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-64</link>
		<dc:creator><![CDATA[Notes on Representation - Tally Marks, Tully Marks &#171; Learning and Unlearning Math]]></dc:creator>
		<pubDate>Thu, 05 Mar 2009 19:54:33 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-64</guid>
		<description><![CDATA[[...] reverse engineering, unlearning by Bert Speelpenning   In previous posts, I looked at tally marks as a representation of quantity.  Well-suited to keeping track of counts, it will yet never [...]]]></description>
		<content:encoded><![CDATA[<p>[...] reverse engineering, unlearning by Bert Speelpenning   In previous posts, I looked at tally marks as a representation of quantity.  Well-suited to keeping track of counts, it will yet never [...]</p>
]]></content:encoded>
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	<item>
		<title>By: Notes on Representation - Tally Marks Ho! &#171; Learning and Unlearning Math</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-61</link>
		<dc:creator><![CDATA[Notes on Representation - Tally Marks Ho! &#171; Learning and Unlearning Math]]></dc:creator>
		<pubDate>Tue, 03 Mar 2009 09:10:09 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-61</guid>
		<description><![CDATA[[...] patterns, models, naming, representations, reverse engineering by Bert Speelpenning   A prior post on tally marks looked at the ease of using tally marks for counting, and its survival as a niche representational [...]]]></description>
		<content:encoded><![CDATA[<p>[...] patterns, models, naming, representations, reverse engineering by Bert Speelpenning   A prior post on tally marks looked at the ease of using tally marks for counting, and its survival as a niche representational [...]</p>
]]></content:encoded>
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		<title>By: Mike</title>
		<link>http://unlearningmath.com/2009/02/28/notes-on-representation-tally-marks/#comment-60</link>
		<dc:creator><![CDATA[Mike]]></dc:creator>
		<pubDate>Sun, 01 Mar 2009 14:53:59 +0000</pubDate>
		<guid isPermaLink="false">http://bertspeelpenning.wordpress.com/?p=682#comment-60</guid>
		<description><![CDATA[Just passing by.Btw, your website have great content!
]]></description>
		<content:encoded><![CDATA[<p>Just passing by.Btw, your website have great content!</p>
]]></content:encoded>
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