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| Quantity and Quality of Information |
Quantity and Quality of Information
The quantity and quality of data available have a direct impact on your ability to solve any related problems. Fans of the old television series, Star Trek, will recall that the computer on the star-ship Enterprise often responded to queries with the phrase ‘insufficient data’ when asked to interpret a perplexing event.
If you were a travel agent, your ability to serve your customers would depend on the range, depth, and accuracy of your knowledge of holiday possibilities. Recommending a beach resort that turned out to be a motel on a rocky shore between two parking lots would not generate many repeat customers.
Sources
The source of new information should be one of your first concerns. Where did the information come from? Can that information be verified by other sources? Where did those sources get their information? Are the sources distinct, or do they all ultimately derive from one source? If so, can that one source be trusted? As a particular item becomes more pivotal in your thinking, it becomes more important for you to confirm that its sources are reliable and independent.
The most reliable information that you can work with is information that you can personally verify. You can talk to the people involved, you can repeat the experiments, you can examine the instruments, and you can test the techniques used to analyze the data.
Accuracy and errors
When the term ‘accurate’ is used to describe information, the implication is that the information is essentially correct.
Observations of physical events always include a variety of possible errors. Errors can be random. For example, if part of an instrument is loose or broken, every measurement can lead to a slightly different result. Errors can be systematic. For example, the end of a ruler maybe worn and then every measurement indicates a length that is slightly too short. Errors can be due to carelessness. For example, a worker may be tired and simply forget to complete one several steps in a procedure.
A golfer estimates the distance to a green, wind speed, and wind direction before selecting a club, lining up the shot, and swinging the club with the required velocity.
Each of those estimates and actions have associated errors. The resulting distance between the ball and the pin provides a concrete measurement of the accuracy for the whole procedure.
Consistency
A procedure is consistent when the same results are obtained over several trials. At a driving range, a golfer’s drives are consistent if they all land relatively close to each other. For example, if nine out of ten drives landed to the left and in front of a target, one could say the golfer’s shots were very consistent, not necessarily accurate, but consistent. Consistency is generally good, because then you can make systematic corrections to improve accuracy. The golfer can adjust her direction of swing towards the right and increase the club velocity slightly. The results should then be both consistent and accurate.
Level of complexity
Some information can be obtained by a simple observation. You can stick your hand out the window to determine if it is raining right now.
Other information may require several observations, assumptions, calculations, and/or indirect measurements. Information derived from complex processes can also be subtle and require several levels of interpretation. For example, before a chemist can describe the average velocity of the atoms in a gas he first has to identify the types of atoms in the gas, measure the temperature and pressure of the gas, and then calculate the average velocity predicted by the ‘speed distribution law for gases’.
Bias
All information has a bias of some kind. All humans generate their own biased view of the world and, intentionally or not, add some of that bias to information that passes through their hands. Your neighbour to the south adds a personal slant when talking about your neighbour to the north. A broadcaster adds bias to the news when selecting which items to include in the evening news. Politicians add bias to information in order to improve their chances of re-election. Theologians bias information to support their views of redemption. Scientists profess to be objective, but on occasion still add subtle bias to information so that it supports their own hard won views of the universe.
Even the reading on your outdoor thermometer on the back porch is biased. Is the thermometer in the shade or in sunlight? Is it near the ground or up near the rafters?
How quickly does it adjust to changes in temperature? How accurately does the reading on the thermometer represent the temperature of the air on the other side of the porch, or across the lawn?
Your challenge is to attain a reasonable assessment of the bias for any particular source of information, and to estimate how that bias may affect your sense of judgement. You should avoid making far-reaching decisions without first taking the bias in your information into account.
The quantity and quality of data available have a direct impact on your ability to solve any related problems. Fans of the old television series, Star Trek, will recall that the computer on the star-ship Enterprise often responded to queries with the phrase ‘insufficient data’ when asked to interpret a perplexing event.
If you were a travel agent, your ability to serve your customers would depend on the range, depth, and accuracy of your knowledge of holiday possibilities. Recommending a beach resort that turned out to be a motel on a rocky shore between two parking lots would not generate many repeat customers.
Sources
The source of new information should be one of your first concerns. Where did the information come from? Can that information be verified by other sources? Where did those sources get their information? Are the sources distinct, or do they all ultimately derive from one source? If so, can that one source be trusted? As a particular item becomes more pivotal in your thinking, it becomes more important for you to confirm that its sources are reliable and independent.
The most reliable information that you can work with is information that you can personally verify. You can talk to the people involved, you can repeat the experiments, you can examine the instruments, and you can test the techniques used to analyze the data.
Accuracy and errors
When the term ‘accurate’ is used to describe information, the implication is that the information is essentially correct.
Observations of physical events always include a variety of possible errors. Errors can be random. For example, if part of an instrument is loose or broken, every measurement can lead to a slightly different result. Errors can be systematic. For example, the end of a ruler maybe worn and then every measurement indicates a length that is slightly too short. Errors can be due to carelessness. For example, a worker may be tired and simply forget to complete one several steps in a procedure.
A golfer estimates the distance to a green, wind speed, and wind direction before selecting a club, lining up the shot, and swinging the club with the required velocity.
Each of those estimates and actions have associated errors. The resulting distance between the ball and the pin provides a concrete measurement of the accuracy for the whole procedure.
Consistency
A procedure is consistent when the same results are obtained over several trials. At a driving range, a golfer’s drives are consistent if they all land relatively close to each other. For example, if nine out of ten drives landed to the left and in front of a target, one could say the golfer’s shots were very consistent, not necessarily accurate, but consistent. Consistency is generally good, because then you can make systematic corrections to improve accuracy. The golfer can adjust her direction of swing towards the right and increase the club velocity slightly. The results should then be both consistent and accurate.
Level of complexity
Some information can be obtained by a simple observation. You can stick your hand out the window to determine if it is raining right now.
Other information may require several observations, assumptions, calculations, and/or indirect measurements. Information derived from complex processes can also be subtle and require several levels of interpretation. For example, before a chemist can describe the average velocity of the atoms in a gas he first has to identify the types of atoms in the gas, measure the temperature and pressure of the gas, and then calculate the average velocity predicted by the ‘speed distribution law for gases’.
Bias
All information has a bias of some kind. All humans generate their own biased view of the world and, intentionally or not, add some of that bias to information that passes through their hands. Your neighbour to the south adds a personal slant when talking about your neighbour to the north. A broadcaster adds bias to the news when selecting which items to include in the evening news. Politicians add bias to information in order to improve their chances of re-election. Theologians bias information to support their views of redemption. Scientists profess to be objective, but on occasion still add subtle bias to information so that it supports their own hard won views of the universe.
Even the reading on your outdoor thermometer on the back porch is biased. Is the thermometer in the shade or in sunlight? Is it near the ground or up near the rafters?
How quickly does it adjust to changes in temperature? How accurately does the reading on the thermometer represent the temperature of the air on the other side of the porch, or across the lawn?
Your challenge is to attain a reasonable assessment of the bias for any particular source of information, and to estimate how that bias may affect your sense of judgement. You should avoid making far-reaching decisions without first taking the bias in your information into account.
