Efficient market theory
Market efficiency refers to the degree to which market prices reflect all available,
relevant information. If markets are efficient, then all information is already
incorporated into prices, and so there is no way to "beat" the market because
there are no undervalued or overvalued securities available. The efficient market
theory hypothesis proposes that financial markets incorporate and reflect all
known relevant information. The validity of an efficient market hypothesis is
debated; however, whether or not the efficient market hypothesis is valid, it is
useful as a theoretical concept with which to study financial market phenomena.
The efficient market hypothesis (EMH), alternatively known as the efficient market
theory, is a hypothesis that states that share prices reflect all information and
consistent alpha generation is impossible.
According to the EMH, stocks always trade at their fair value on exchanges, making it
impossible for investors to purchase undervalued stocks or sell stocks for inflated
prices. Therefore, it should be impossible to outperform the overall market through
expert stock selection or market timing, and the only way an investor can obtain
higher returns is by purchasing riskier investments.
Although it is a cornerstone of modern financial theory, the EMH is highly
controversial and often disputed. Believers argue it is pointless to search for
undervalued stocks or to try to predict trends in the market through either
fundamental or technical analysis.
According to E.F Fama “efficient market is defined as the market there are a large
number of rational profit maximizers actively competing with each trying to predict
even the market value of individual securitizes and where current information is
almost freely available to all participants”
Market Efficiency hypothesis
There are three degrees of market efficiency. The weak form of market efficiency is
that past price movement are not useful for predicting future prices. If all available,
relevant information is incorporated into current prices, then any information
relevant information that can be gleaned from past prices is already incorporated
into current prices. Therefore, future price changes can only be the result of new
information becoming available.
Based on this form of the hypothesis, such investment strategies as momentum or
any technical-analysis-based rules used for trading or investing decisions should not
be expected to persistently achieve above normal market returns. Within this form of
the hypothesis, there remains the possibility that excess returns might be possible
using fundamental analysis. This point of view has been widely taught in academic
finance studies for decades, though this point of view is no longer held so
dogmatically.
The semi-strong form of market efficiency assumes that stocks adjust quickly to
absorb new public information so that an investor cannot benefit over and above the
market by trading on that new information. This implies that neither technical
analysis nor fundamental analysis would be reliable strategies to achieve superior
returns because any information gained through fundamental analysis will already be
Market efficiency refers to the degree to which market prices reflect all available,
relevant information. If markets are efficient, then all information is already
incorporated into prices, and so there is no way to "beat" the market because
there are no undervalued or overvalued securities available. The efficient market
theory hypothesis proposes that financial markets incorporate and reflect all
known relevant information. The validity of an efficient market hypothesis is
debated; however, whether or not the efficient market hypothesis is valid, it is
useful as a theoretical concept with which to study financial market phenomena.
The efficient market hypothesis (EMH), alternatively known as the efficient market
theory, is a hypothesis that states that share prices reflect all information and
consistent alpha generation is impossible.
According to the EMH, stocks always trade at their fair value on exchanges, making it
impossible for investors to purchase undervalued stocks or sell stocks for inflated
prices. Therefore, it should be impossible to outperform the overall market through
expert stock selection or market timing, and the only way an investor can obtain
higher returns is by purchasing riskier investments.
Although it is a cornerstone of modern financial theory, the EMH is highly
controversial and often disputed. Believers argue it is pointless to search for
undervalued stocks or to try to predict trends in the market through either
fundamental or technical analysis.
According to E.F Fama “efficient market is defined as the market there are a large
number of rational profit maximizers actively competing with each trying to predict
even the market value of individual securitizes and where current information is
almost freely available to all participants”
Market Efficiency hypothesis
There are three degrees of market efficiency. The weak form of market efficiency is
that past price movement are not useful for predicting future prices. If all available,
relevant information is incorporated into current prices, then any information
relevant information that can be gleaned from past prices is already incorporated
into current prices. Therefore, future price changes can only be the result of new
information becoming available.
Based on this form of the hypothesis, such investment strategies as momentum or
any technical-analysis-based rules used for trading or investing decisions should not
be expected to persistently achieve above normal market returns. Within this form of
the hypothesis, there remains the possibility that excess returns might be possible
using fundamental analysis. This point of view has been widely taught in academic
finance studies for decades, though this point of view is no longer held so
dogmatically.
The semi-strong form of market efficiency assumes that stocks adjust quickly to
absorb new public information so that an investor cannot benefit over and above the
market by trading on that new information. This implies that neither technical
analysis nor fundamental analysis would be reliable strategies to achieve superior
returns because any information gained through fundamental analysis will already be
