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| Types of Information |
Types of Information
First you have to decide what type of information you are dealing with.
Data versus information
Data is collected from basic observations; typically personal accounts or readings from instruments such as a thermometer, a ruler, or a weigh scale. Raw data does not become information until it has been filtered, processed, and interpreted.
Filtering data involves removing obvious errors (someone recorded the data in reverse order, or used the Fahrenheit rather than the Celsius scale). Processing data involves sorting data into categories, making tallies in those categories, and making preliminary calculations. In preparing your taxes you have to sort all your slips for income and all your receipts for expenditures into categories and add them up.
Interpreting data involves comparing observed data values with expected values based on past experience. Then you can make statements such as ‘serious crime is down’, ‘poverty is up’, or ‘the volcano is about to erupt’.
By the time raw data has been converted into information, it has usually been massaged into a familiar format. Often this process works so well that you are not aware that information may have been subtly modified to meet your expectations. On occasion, the conversion of data can even result in information that is in conflict with reality. You need to be aware of this possibility and should always be prepared to double check data, procedures, and assumptions.
Sources of information
Information can come from a variety of sources, and each source can have its own strengths and weaknesses.
First you have to decide what type of information you are dealing with.
Data versus information
Data is collected from basic observations; typically personal accounts or readings from instruments such as a thermometer, a ruler, or a weigh scale. Raw data does not become information until it has been filtered, processed, and interpreted.
Filtering data involves removing obvious errors (someone recorded the data in reverse order, or used the Fahrenheit rather than the Celsius scale). Processing data involves sorting data into categories, making tallies in those categories, and making preliminary calculations. In preparing your taxes you have to sort all your slips for income and all your receipts for expenditures into categories and add them up.
Interpreting data involves comparing observed data values with expected values based on past experience. Then you can make statements such as ‘serious crime is down’, ‘poverty is up’, or ‘the volcano is about to erupt’.
By the time raw data has been converted into information, it has usually been massaged into a familiar format. Often this process works so well that you are not aware that information may have been subtly modified to meet your expectations. On occasion, the conversion of data can even result in information that is in conflict with reality. You need to be aware of this possibility and should always be prepared to double check data, procedures, and assumptions.
Sources of information
Information can come from a variety of sources, and each source can have its own strengths and weaknesses.
First hand versus indirect
Information can be derived from first-hand sources: people who were actually present when an event occurred, or from others who have already gathered accounts of events from a variety of sources. In history texts, most accounts are based on second or third hand descriptions, and previously published summaries.
Trained observer versus casual observer
Even a first-hand account is not necessarily a good source of information. If you have ever watched television interviews with witnesses to an event, you know that their responses tend to emphasize their own emotions and observations from a narrow point of view. In contrast, trained observers look for significant factors in the events taking place around them.
Suppose a meteor has just crashed into a parking lot. A casual observer might say, ‘I was just coming out of the laundromat when there was this bright flash of light over that way and then there was a loud crash and dirt was flying everywhere. The dog next door started to howl.’ A trained observer might be able to add, ‘There was a flash of light in the north-east, brighter than the Sun, accompanied by a roar like a freight train, followed by an impact in the parking lot that left a hole about two metres deep and twice as wide. The ground was so hot the asphalt was melted for another three metres around the crater.’
Measured versus estimated
Information based on measurements is generally more accurate than personal estimates. An instrument simply provides numbers on a standard scale, without any emotional content. Records of instrument readings tend to remain constant over time, whereas mental estimates tend to vary in the direction of the more dramatic over time.
The information in the meteor impact example would have been even more reliable if an observer had used instruments to measure the path of the meteor, the size of the crater, and the temperature of the surroundings.
Unique versus repeatable
Information can be based on unique one-time events such as an artistic performance, or the devastation of an earthquake. If you were not there at that time, you missed the event and have to rely on the accounts of others.
Most of our information about the world around us is derived from continuous or frequent events, such as the height of tides or the magnitude of the electric charge on an electron. Observations that can be repeated and measured with instruments are generally more reliable.
Ultimately the interpretation of data involves assumptions, analysis, experience, and judgement. It is still possible for different people to reach diverse conclusions based on the same original data.
Information can be derived from first-hand sources: people who were actually present when an event occurred, or from others who have already gathered accounts of events from a variety of sources. In history texts, most accounts are based on second or third hand descriptions, and previously published summaries.
Trained observer versus casual observer
Even a first-hand account is not necessarily a good source of information. If you have ever watched television interviews with witnesses to an event, you know that their responses tend to emphasize their own emotions and observations from a narrow point of view. In contrast, trained observers look for significant factors in the events taking place around them.
Suppose a meteor has just crashed into a parking lot. A casual observer might say, ‘I was just coming out of the laundromat when there was this bright flash of light over that way and then there was a loud crash and dirt was flying everywhere. The dog next door started to howl.’ A trained observer might be able to add, ‘There was a flash of light in the north-east, brighter than the Sun, accompanied by a roar like a freight train, followed by an impact in the parking lot that left a hole about two metres deep and twice as wide. The ground was so hot the asphalt was melted for another three metres around the crater.’
Measured versus estimated
Information based on measurements is generally more accurate than personal estimates. An instrument simply provides numbers on a standard scale, without any emotional content. Records of instrument readings tend to remain constant over time, whereas mental estimates tend to vary in the direction of the more dramatic over time.
The information in the meteor impact example would have been even more reliable if an observer had used instruments to measure the path of the meteor, the size of the crater, and the temperature of the surroundings.
Unique versus repeatable
Information can be based on unique one-time events such as an artistic performance, or the devastation of an earthquake. If you were not there at that time, you missed the event and have to rely on the accounts of others.
Most of our information about the world around us is derived from continuous or frequent events, such as the height of tides or the magnitude of the electric charge on an electron. Observations that can be repeated and measured with instruments are generally more reliable.
Ultimately the interpretation of data involves assumptions, analysis, experience, and judgement. It is still possible for different people to reach diverse conclusions based on the same original data.
