29 Matching Annotations
  1. Last 7 days
    1. This second assumption, called diminishing marginal utility, will imply ‘risk aversion’!

      A student asked

      I want to ask why risk-averse has a decreasing marginal utility? Thank you.

      Response:

      If someone has a decreasing marginal utility of income and they maximise expected utility then they will be risk averse.

      This is something that takes a long time to fully explain, and I try to give an explanation in the web-book and in lecture (and again in tomorrow's lecture).

      One simple intuition.: Risk averse essentially means "I will never take any fair gamble".

      E.g., "I'll never accept a bet with an equal chance of losing or gaining some amount X." How does diminishing MU of income explain this? If I have diminishing MU of income then my utility is increasing in income at a decreasing rate.

      The first units of income (e.g., going from 0 income to 15k income) add more utility than the later units of income (e.g., going from 15k income to 30k income) , which adds more than even later increments (e.g., going from 30k to 45k), etc.

      So "an equal chance of losing or gaining X" would not be attractive to such a person. Why not? Because relative to any point "losing X" reduces my utility more than "gaining X" increases it.

      E.g., in the above example, if you started at 15K income you wouldn't want to have an equal chance of losing or gaining 15K in income. Having 0 income would be terrible, while having 30k income would be better, but not 'that much' better. As we said, the utility difference between 0 and 15K is much greater than the utility difference between 15k and 30k... because of the assumption of diminishing marginal utility. So it's better to have 15k for sure than to have a 50/50 chance of 0k or 30k.

      The 'utility loss from losing 15k' is greater than the 'utility gain from gaining 15k'. As expected utility weights the utility of each outcome by its probability and sums these, in considering a 1/2 chance of losing 15k and a 1/2 chance of gaining 15k these probabilities weight equally, so I only need to consider "does the utility cost of losing 15k exceed the utility gain from gaining 15k" in this example. Because of diminishing MU, we know it does not. Nor does it for any "equal chance of losing or gaining some amount X". Thus this person is risk-averse.

      I hope this helps. Looking at the 'utility of income' diagrams may also be helpful.

  2. Oct 2019
    1. First, government did not always engage with the market early in running procurements or establish a sufficient understanding on both sides about the service that were being outsourced. This often led to problems over the lifetime of a contract, such as disputes and cost overruns.Second, an excessive focus on the lowest price and an insufficient assessment of quality in selecting bids undermined many contracts. While outsourcing can reduce costs, government must balance this against the minimum level of quality it needs in a service. Too often, it has outsourced services in pursuit of unrealistic savings and without a realistic expectation that companies would deliver efficiencies.Third, large contracts have failed when government has transferred risks that suppliers have no control over and cannot manage, rather than those which suppliers can price and manage better than government. Government should also not think that it has outsourced risks that will revert to it if a supplier fails – as the provision of public services will always do.

      Three case study themes on why contracts failed or worked

  3. Sep 2019
  4. Jul 2019
    1. Fellow student, since you are reading this, you installed Hypothes.is as the instructor's recommended. However, the extension by default has permissions to read all data on all websites you visit. Technically that means email, banking sites, etc. I for one don't want to give random software that authority. The developer did provide a easy way to limit that, and I'll assume he programmed it to work as promised. If you right click on the "h." extension icon, you can change "This can read and write all site data" to only Coursera - which means you can use the extension for the class, but it shouldn't be reading your emails or bank passwords.

      For the course writers and INSEAD - while Hypothesis looks solid and its nice that its non-profit, encouraging all students to install unrestricted extensions which can read all pages and data is a big responsibility, it could easily go wrong. Have you considered how this could be used as malware with the extensive permissions the extension is granted by default?

  5. Jun 2019
    1. “I felt like it wasn’t taken care of and it didn’t feel any safer to me and it didn’t feel any safer to (my son),”

      In most cases, many parents in this situation can understand all too well with the safety of their child. According to the school, the case is resolved with a slap on the wrist for the offender. Amy and her son still feels unsafe. Jacob would have to go to school everyday with fear waiting for the next bad thing to happen. Aside from that, parents must also fear the risk of suicide and the mental well being of their child? The result of a case being "resolved."

    1. volatility and leverage are co-determined and arepro-cyclical; that is, together, they amplify the impact ofshocks. The mechanism, to be specific, is that decliningvolatility reduces the cost of taking on more leverage andfurthers a buildup of risk. The lesson: Risk managers mustresist the temptation to sell volatility when it is low andfalling. The AMH implicitly embraces modeling suchbehavior with heterogeneous agents that use heuristics.
  6. May 2019
    1. first target the patients at highest risk of relapse;

      Clinical trials will most certainly first include those patients with the highest risk of relapse. However, long term, everything will depend on the risk/ benefit trade off: if an effective, simple, well-tolerated and cost-effective treatment was available (let's imagine a single short low-dose PD1 for any early Melanoma patient) that prevented progression for most patients would be very different from a highly toxic, expensive treatment that doesn't work for everyone (think Ipi 10mg/kg adjuvant)- so everything is in the trade-off

  7. Jan 2019
    1. priori. Such is the situation with disaster.We easily dismisshow uncertainsituations of disaster areor can become, and how a goalin safety-critical work is to avert situations beforethey become problems. Much of the work in safety-and time-critical matters in CSCW appreciates the implications of this goalon vigilance, mutual awareness, and, of course, error, especially propagated error. It is all too easy to blame “pilot error” when a sequence of preceding systemic conditions took place to set a pilot up for perceiving the problem as he or she did [34,48], including one that warns of hazard. Indeed, disaster can magnifyproblems, not necessarily out of proportion, though that can happen, but rather too so that wefocusonspecific detailswhen many things are happening.

      Evokes distributed cognition (Hutchins) as well as the uncertain nature of safety- and time-critical work and how to classify risk/need.

  8. Oct 2018
  9. Aug 2018
    1. Indeed, school exclusion, without these supports, can exacerbate a bad situation. In the Parkland case, the fact that Nikolas Cruz had been expelled from school may have contributed to driving an angry young man who felt isolated to take out his frustration and anger by killing students and staff at his former school. In theory, zero-tolerance policies deter students from violent or illegal behavior because the punishment for such a violation is harsh and certain. However, research shows that such policies ultimately increase illegal behavior and have negative effects on student academic achievement, attainment, welfare, and school culture.
  10. Nov 2017
    1. A visual exploration of the link between statin use and the risk of Diabetes in a subpopulation of patients with subclinical hypothyroidism.

      This is an interactive graph created with Biovista Vizit; nodes and links can be further explored to view supporting bibliography and molecular mechanism of action.

  11. May 2017
    1. Using data from a large Danish health study, researchers have found an association between chocolate consumption and a lowered risk for atrial fibrillation, the irregular heartbeat that can lead to stroke, heart failure and other serious problems.
    1. RESULTS: After adjustment for potential confounders, use of azithromycin (adjusted odds ratio [OR] 1.65, 95% confidence interval [CI] 1.34–2.02; 110 exposed cases), clarithromycin (adjusted OR 2.35, 95% CI 1.90–2.91; 111 exposed cases), metronidazole (adjusted OR 1.70, 95% CI 1.27–2.26; 53 exposed cases), sulfonamides (adjusted OR 2.01, 95% CI 1.36–2.97; 30 exposed cases), tetracyclines (adjusted OR 2.59, 95% CI 1.97–3.41; 67 exposed cases) and quinolones (adjusted OR 2.72, 95% CI 2.27–3.27; 160 exposed cases) was associated with an increased risk of spontaneous abortion.

      This shows between a 65% to 272% increased risk of miscarriage from use of common antibiotics.

      The risk is being characterized as "small' - http://www.cnn.com/2017/05/01/health/antibiotics-miscarriage-study/

      I'm not sure any pregnant woman would characterize more than doubling of the risk as small, and we can assume that if this data was shown for a natural substance, it would be characterized differently.

  12. Mar 2017
    1. 9. And regular orgasms can reduce the risk of prostate cancer.

      The study that is hyperlinked in this article takes you to a blog post on the Harvard Medical School Prostate Knowlegde blog. They didn't do the study, but they wrote a post about two studies that were conducted on the topic and gave references, which made it nice to follow. After reading the two studies, i found that this title tends to be misleading in its statement. Both studies conducted found that men who ejaculate more than either 7 times per week or more than 21 times a month have a decreased risk of prostate cancer. To me, this is not regular orgasms, that amount seems to be on the higher end for most people and hard to continue through out your life. In conclusion, yes, more ejaculations can reduce your risk of prostate cancer, but the amount needed is high and must be started at a young age to fully reap the benefits.

      APA References:

      Giles, G.G., Severi, G., English, D.R., McCredie, M.R.E., Borland, R., Boyle, P., & Hopper, J.L. (2003). Sexual factors and prostate cancer. BJU International, 92(3), 211-216.

      Leitzmann, M.F., Platz, E.A., Stampfer, M.J., Willett, W.C., Giovannucci, E. (2004). Ejaculation frequency and subsequent risk of prostate cancer. JAMA: Journal of the American Medical Association, 291(13), 1578-1586.

      Links: http://jamanetwork.com/journals/jama/fullarticle/198487?=quot;,gt;

      http://onlinelibrary.wiley.com/doi/10.1046/j.1464-410X.2003.04319.x/full

    1. alone

      Another facet/form of risk.

    2. risky

      I think this is key. The only alternative to argument is a risk--to risk one's self by making their narrative plain and facing the possibility that the other will reject one's narrative (and thereby reject one's personhood.

      The difference between the previous steps to avoid argument and this one is that this one advocates risk and seems to make no promise of resolution.

    1. With only an hour face-to-face meeting with my friend Claude Tregoat we set up connections for 500 students in a project which would become to be known as CLAVIER.

      Taking the risk to be open.

      Feeling of being uncomfortable when first confronted with explaining a potential project - that reminds me of conversations with Maritta and Leena.

    1. The plan should also include a discussion about any possible unintended consequences and steps your institution and its partners (such as third-party vendors) can take to mitigate them.

      Need to create a risk management plan associated with the use of predictive analytics. Talking as an organization about the risks is important - that way we can help keep each other responsible for using analytics in a responsible way.

    1. algal

      Algal bloom is noted by the EPA as a major environmental problem. Essentially, algal blooms are overgrowths of algae. Of course, a natural phenomenon such as this does not know political boundaries, and thus information given on Algal Bloom by the EPA is as valid in Canada as it is in the U.S. Algal blooms are also known as red tides, cyanobacteria, or blue-green algae. Algal blooms are commonly toxic, and the EPA advises people and other animals stay away from water sources that look like they may have algal bloom occurring. This water is commonly green, bad smelling, or scummy. Algal bloom can occur in both marine environments and fresh water environments. In fact, in both these environments, even non-toxic algal blooms can affect the economy and environment. This is because algal blooms can create “dead zones” in the environment they are present in. They also make treatment of drinking water much harder, raising costs of that process. They also hurt industries that rely on clean water to operate. Algal blooms essentially need three things to occur: slow moving water, sunlight, and nutrients. These nutrients include nitrogen and phosphorus. In terms of specific effects of the harmful algal bloom, the human health consequences can be seen as symptoms such as: respiratory problems, stomach illness, liver illness, rashes, and neurological effects. Children drinking nitrates (a common element in algal bloom water) is also very dangerous. Dioxins, which are used to treat water contaminated with the elements of algal bloom, can also be dangerous.

      EPA. “Harmful Algal Blooms”. Last modified January 23, 2017. https://www.epa.gov/nutrientpollution/harmful-algal-blooms

  13. Feb 2017
  14. Jan 2017
  15. Dec 2016
  16. Oct 2016
    1. didn’t want to stir up trouble in their future classrooms

      it's a shame that teachers may be hesitant to elevate the discourse amongst students out of fear of repercussions due to idealogy

  17. Feb 2014
    1. The Backblaze environment is the exact opposite. I do not believe I could dream up worse conditions to study and compare drive reliability. It's hard to believe they plotted this out and convened a meeting to outline a process to buy the cheapest drives imaginable, from all manner of ridiculous sources, install them into varying (and sometimes flawed) chassis, then stack them up and subject them to entirely different workloads and environmental conditions... all with the purpose of determining drive reliability.

      The conditions and process described here mirrors the process many organizations go through in an attempt to cut costs by trying to cut through what is perceived as marketing-hype. The cost differences are compelling enough to continually tempt people down a path to considerably reduce costs while believing that they've done enough due-diligence to avoid raising the risk to an unacceptable level.

    1. The conservative influence of property does not, however, depend on primogeniture or even inheritance -- features that gave property a valuable role in Burke's political system as well as in the political theories advanced by Hegel and Plato. n11 Within a single lifetime, property tends to make the property owner more risk-averse. This aversion applies both to public decisions [*291] affecting property, such as taxes, and to personal decisions that might diminish one's property, such as investment strategies and career choices. Inheritance and capital appreciation are only additional characteristics of traditional notions of property that tend to stabilize social stratification.