StudentsEducators

Pagerank Algorithm

The PageRank algorithm is a method used to rank web pages in search engine results, developed by Larry Page and Sergey Brin, the founders of Google. It operates on the principle that the importance of a webpage can be determined by the quantity and quality of links pointing to it. Each link from one page to another is considered a "vote" for the linked page, and the more votes a page receives from highly-ranked pages, the more important it becomes. Mathematically, the PageRank RRR of a page can be expressed as:

R(A)=(1−d)+d∑i=1NR(Ti)C(Ti)R(A) = (1 - d) + d \sum_{i=1}^{N} \frac{R(T_i)}{C(T_i)}R(A)=(1−d)+di=1∑N​C(Ti​)R(Ti​)​

where:

  • R(A)R(A)R(A) is the PageRank of page A,
  • ddd is a damping factor (usually set around 0.85),
  • TiT_iTi​ are the pages that link to page A,
  • R(Ti)R(T_i)R(Ti​) is the PageRank of page TiT_iTi​,
  • C(Ti)C(T_i)C(Ti​) is the number of outbound links from page TiT_iTi​.

This formula iteratively calculates the PageRank until it converges, which reflects the probability of a random surfer landing on a particular page. Overall, the algorithm helps improve the relevance of search results by considering the interconnectedness of web pages.

Other related terms

contact us

Let's get started

Start your personalized study experience with acemate today. Sign up for free and find summaries and mock exams for your university.

logoTurn your courses into an interactive learning experience.
Antong Yin

Antong Yin

Co-Founder & CEO

Jan Tiegges

Jan Tiegges

Co-Founder & CTO

Paul Herman

Paul Herman

Co-Founder & CPO

© 2025 acemate UG (haftungsbeschränkt)  |   Terms and Conditions  |   Privacy Policy  |   Imprint  |   Careers   |  
iconlogo
Log in

Moral Hazard

Moral Hazard refers to a situation where one party engages in risky behavior or fails to act in the best interest of another party due to a lack of accountability or the presence of a safety net. This often occurs in financial markets, insurance, and corporate settings, where individuals or organizations may take excessive risks because they do not bear the full consequences of their actions. For example, if a bank knows it will be bailed out by the government in the event of failure, it might engage in riskier lending practices, believing that losses will be covered. This leads to a misalignment of incentives, where the party at risk (e.g., the insurer or lender) cannot adequately monitor or control the actions of the party they are protecting (e.g., the insured or borrower). Consequently, the potential for excessive risk-taking can undermine the stability of the entire system, leading to significant economic repercussions.

Elasticity Demand

Elasticity of demand measures how the quantity demanded of a good responds to changes in various factors, such as price, income, or the price of related goods. It is primarily expressed as price elasticity of demand, which quantifies the responsiveness of quantity demanded to a change in price. Mathematically, it can be represented as:

Ed=% change in quantity demanded% change in priceE_d = \frac{\%\ \text{change in quantity demanded}}{\%\ \text{change in price}}Ed​=% change in price% change in quantity demanded​

If ∣Ed∣>1|E_d| > 1∣Ed​∣>1, the demand is considered elastic, meaning consumers are highly responsive to price changes. Conversely, if ∣Ed∣<1|E_d| < 1∣Ed​∣<1, the demand is inelastic, indicating that quantity demanded changes less than proportionally to price changes. Understanding elasticity is crucial for businesses and policymakers, as it informs pricing strategies and tax policies, ultimately influencing overall market dynamics.

Keynesian Beauty Contest

The Keynesian Beauty Contest is an economic concept introduced by the British economist John Maynard Keynes to illustrate how expectations influence market behavior. In this analogy, participants in a beauty contest must choose the most attractive contestants, not based on their personal preferences, but rather on what they believe others will consider attractive. This leads to a situation where individuals focus on predicting the choices of others, rather than their own beliefs about beauty.

In financial markets, this behavior manifests as investors making decisions based on their expectations of how others will react, rather than on fundamental values. As a result, asset prices can become disconnected from their intrinsic values, leading to volatility and bubbles. The contest highlights the importance of collective psychology in economics, emphasizing that market dynamics are heavily influenced by perceptions and expectations.

Ldpc Decoding

LDPC (Low-Density Parity-Check) decoding is a method used in error correction coding, which is essential for reliable data transmission. The core principle of LDPC decoding involves using a sparse parity-check matrix to identify and correct errors in transmitted messages. The decoding process typically employs iterative techniques, such as the belief propagation algorithm, where messages are passed between variable nodes (representing bits of the codeword) and check nodes (representing parity checks).

During each iteration, the algorithm refines its estimates of the original message by updating beliefs based on the received signal and the constraints imposed by the parity-check matrix. This process continues until the decoded message satisfies all parity-check equations or reaches a maximum number of iterations. The efficiency of LDPC decoding arises from its ability to achieve performance close to the Shannon limit, making it a popular choice in modern communication systems, including satellite and wireless networks.

Mundell-Fleming Trilemma

The Mundell-Fleming Trilemma is a fundamental concept in international economics, illustrating the trade-offs between three key policy objectives: exchange rate stability, monetary policy autonomy, and international capital mobility. According to this theory, a country can only achieve two of these three goals simultaneously, but not all three at once. For instance, if a country opts for a fixed exchange rate and wants to maintain capital mobility, it must forgo independent monetary policy. Conversely, if it desires to control its monetary policy while allowing capital to flow freely, it must allow its exchange rate to fluctuate. This trilemma highlights the complexities that policymakers face in a globalized economy and the inherent limitations of economic policy choices.

Protein Folding Stability

Protein folding stability refers to the ability of a protein to maintain its three-dimensional structure under various environmental conditions. This stability is crucial because the specific shape of a protein determines its function in biological processes. Several factors contribute to protein folding stability, including hydrophobic interactions, hydrogen bonds, and ionic interactions among amino acids. Misfolded proteins can lead to diseases, such as Alzheimer's and cystic fibrosis, highlighting the importance of proper folding. The stability can be quantitatively assessed using the Gibbs free energy change (ΔG\Delta GΔG), where a negative value indicates a spontaneous and favorable folding process. In summary, the stability of protein folding is essential for proper cellular function and overall health.