February 15, 2014
I recently gave a talk about algorithms to a 6-th grade class. My slides are below (an English version and a Hebrew version).
What I believe worked very well was going through the execution of the algorithms step-by-step and having the kids take turns at saying in advance, before I switch to the next slide, what the changes they are expecting see are – where the instruction pointer arrow will move, what variables will change their values and what new output will be emitted.
February 3, 2014
I have spent my childhood and adolescence implicitly believing in ideas about learning that in later life I have come to disbelieve. It appears to me that those ideas are quite common in our society, including among schoolchildren. These false ideas cause significant harm to many of those who believe in them and, being widespread, to society. I therefore think it is important to disabuse students, and particularly children, of these ideas.
The false ideas about learning maintain their hold in the mind of the public mainly because they are rarely examined. One of the false ideas is that the nature of learning is self-evident and needs no examination. This, of course, makes those ideas self-reinforcing.
This essay is a brief description of those erroneous ideas about learning and of an alternative view – in my opinion, the correct view. To make things concrete, I start by listing a set of practical implications of the rejection of the false notions and adoption of the alternative view. These are things that can and should be done by the various people involved in education – students, teachers, and managers of education systems.
January 31, 2014
August 28, 2013
Apartment prices in Israel have gone up significantly in recent years. In the years 1996 to 2008, an average apartment cost about 100 average salaries. Within two years, this ratio has gone up to about 130. This rise can be explained to a significant extent by the reduction in interest rates, which implies that a given mortgage payment can repay higher loans. The interest rate on an indexed 20 year mortgage has fallen from about 6% in the late 1990’s and early 2000’s to about 3.5% in 2010 to 2012. As a result, despite the 30% increase in apartment cost to salary ratio, the ratio of the monthly payment on a 20 year loan for the cost of an average apartment to the average salary has gone up much more moderately – from about 70% to about 80%.
The fact that the increase in apartment prices is associated with a decrease in interest rates raises the possibility that a future rise in the interest rates (which would bring them close to historical rates) would cause a return of the apartment cost to salary ratio to its previous level.
- Average monthly salary (nominal): Social security data (social security law, section 1), similar to statistical abstract 2012, Table 12.34, but more up to date, using the January 1st 2013 entry as reflecting 2012 data, etc.
- Consumer price index (CPI): Israeli central bureau of statistics (CBS), series 120010
- Average price of apartment owned by its residents: CBS series 020000
- 20-year mortgage CPI-indexed interest rate: Bank of Israel data, using the “20-25 years” column for recent years and the “above 20 years” column for pre-July 2011 entries
Co-authored with Daniel Gat.
May 4, 2013
Note: The data here do not include settlers and construction in the eastern neighborhoods of Jerusalem, i.e., those areas of the West Bank that are included by Israel in the municipal boundaries of Jerusalem.
January 26, 2013
The increase of the Haredi (Jewish ultra-orthodox) population in Israel is a topic widely discussed in Israeli mass media and with considerable sway over Israeli politics both in the form of increasing Haredi electoral power and in the form of providing campaign and policy agendas for opposing forces.
Official statistics (social security annual report 2011, charts on pages 139, 140) indicate that the average Haredi family has about 6 children (with a decreasing trend over the last two decades) while non-Haredi Jewish families have about 2.5 children. Talk about demographic trends caused by the differential fertility rate, causing an imminent “Haredi and Arabic” majority, is quite common. This is coupled with complaints about the fact that Haredi labor force participation rate is low, the fact that Haredim do not serve in the Israeli military and the fact that some Haredim receive stipends from the state as rabbinical students.
The chart below shows the proportion of votes received by Haredi parties in Israeli elections.
September 30, 2012
Whatever Marx and Engels may have thought about the future of the state, the real question is not whether a public power will be needed in a classless society, but whether that public power will constitute a problem. In other words, are there certain problems inherent in public power itself whether or not it is class power? I take it for granted that it is hopelessly naive to believe in an advanced socialist society administered by simple forms of direct and spontaneous democracy. It is difficult to avoid the conviction that even classless society will require some form of representation, and hence authority and even subordination of some people to others. That premise granted, it must be added that, whether or not one uses the term “state” to describe political and administrative power in a classless society, it seems unduly optimistic to believe that there can ever be a case in which power exercised by some people on behalf of others does not constitute a problem. Socialist political theory must, therefore, face the problems posed by representation, authority, and subordination, and the fact that their very existence makes possible the misappropriation of power.
Ellen Meiksins Wood
C.B. MACPHERSON: LIBERALISM, AND THE TASK OF SOCIALIST POLITICAL THEORY
THE SOCIALIST REGISTER 1978
April 12, 2012
I recently came across a site with some promise – Radical Philosophy magazine. The current issue has an interview with Noam Chomsky discussing, among other things, Free Will. I found that I do not agree, and to some extent do not understand, his position. This serves as an excuse to present my theory of Free Will.
I will grant at the outset that I am not well read on the subject. I have never read, for example, Descartes’s theories on this issue. My theory is very simple, but, I think, is quite serviceable in dealing with the limited issue of Free Will. It does not address the matter of consciousness, which I think is more complex.
My understanding is that:
Free Will is that part of a decision making process or action generation process that is inexplicable to the observer.
November 26, 2011
It is fair to say, I think, that over the last 40 years or so there has been little progress in the quality of life of the average person in the West, and quite possibly there has been a deterioration. (The only indicator in which there has been steady progress, I think, is longevity.1)
Progressive ideology generally asserts that there is a wide variety of elements of conceivable and feasible policy and technology that would significantly improve average quality of life. It may be further assumed that the pursuit of any of those elements or any combination of those elements can be expected to be fruitful. To some extent this assumption – what may be termed the “parallel progress assumption” – seems to be implicit in much of present-day progressive activism: the agenda is usually very eclectic and often somewhat vague on specifics. While this is partly a tactic that is aimed at maintaining wide appeal, there is also the implication that as long as general principles are agreed to, laying out a detailed workplan is not necessary since progress can be made on any of many items quite independently of each other. While I accept the progressive assumption (i.e., that progress is possible) it appears to me that the parallel progress assumption is incorrect.
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Deviations from the mean of a sum of independent, non-identically-distributed Bernoulli variables, continued
October 29, 2011
Continuing the investigation initiated here, and applying the same notation.
For every l, l >= ES, P(S ≥ l) is maximized when q1 = ··· = qn-mz = q = ES / (n – mz), and qn – mz + 1 = ··· = qn = 0, for some mz.
That is, in the terminology of Proposition 1, for all non-trivial cases, mo = 0, and thus the probability of deviation is maximized by some Bernoulli variable (rather than a shifted Bernoulli variable).
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