Brainstorm here Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments.
Gives some examples here – medical experiments, horticulture and agriculture
You might be wondering how you can see 2 or 3 commercials in a row for toothpaste and toothbrushes and all of them can say that 9 out of 10 dentists say they would recommend it to their own patients. This is a very popular form of misleading statistic called selection bias. Selection bias happens when an unrepresentative population has been taken for a survey or study and then the results are advertised to the public consumers as if it represented the total population(Whitman 154). Sometimes this can be accidental, even to companies themselves. For Example, a company might decided to do an online survey to see how consumes like their newest product. This sounds like a perfectly constructed survey, but it is actually very skewed due to selection bias. Since the survey is conducted online only people with computers and internet can respond (Whitman 155). Most Americans today do not have both of these luxeries. Also, the people that do have both a computer and internet will generally get on the computer more than just once a day. Selection bias is a very difficult type of misleading statistic to catch, and therefore a favorite of drug and hygiene products. The FDA has only allowed these companies to advertise on television since 1997, but since then they have come to dominate a good percentage of the commercials shown on television. Today these drug and hygiene companies are coming out with commercials left and right that state incredibly high results toward their product. In many of these commercials you will hear the narrator say that, "These results are based on a survey conducted.... blah blahblah". The problem is that we do not generally pay any attention to these bits of information because we have already seen a number of commercials, or because we are thinking of something else at the moment. Normally, people would argue, this is not a big problem because we were not planning on buying any of these products anytime soon. This is not an incorrect statement, you are probably not going to stop what you are doing to go buy some Crest toothpaste. However, when we see the same toothpaste commercial hundreds of times, even if we do not think you we are paying attention to them, we are all more likely to pick that type of toothpaste up the next time you are at the store. This type of unconscious, almost mind-washing, reaction that these advertisements have on consumers might sound a little frightening, but not to fear, I would not leave you without a couple simple and effective solutions:The next time you see a commercial saying that 9 out of 10 dentists would recommend a certain brand of toothbrush, listen to how they conducted this survey; also, take the statistic with a grain of sand, understanding now how easy it is to come up with such a statistic. Instead of never paying attention to these types of commercials, listen to that toothpaste commercial that you have seen over 100 times. It will only take one or two times of actually actively listening to the commercial for you to completely understand the commercial and its statistics. Since you have now actively thought about this information, it is near-impossible for the information to subconsciously convince you of anything.
Activity 1 See task sheet for more details. Show friends video on youtube or direct from media file
Show video here- direct media file is available
There are three kinds of lies
Popularized by Mark TwainTwisting information to youradvantage…
What’s so good about Statistics? Statistics give us a way to look at the big picture and get a much more accurate way of understanding what is going on in the world than what we could get from individual observations.
Misleading Statistics inAdvertising This toothpaste is recommended by nine out of ten dentists! Is this true?
Misleading Statistics inAdvertising Statistics are a good way to show facts in an easy- to-understand format, such as a percentage. This has proven extremely successful because we, as consumers, like to believe all statistics are completely true
Problems With Statistics While statistics are extremely valuable, they are also notorious for being a means that people use to make false and misleading arguments. There are some main ways to manipulate statistics The toothpaste advertisement is an example of selection bias.
Selection Bias A good sample is representative. This means that each sample (person) represents the attributes of a known number of population. Bias often occurs when the survey sample does not accurately represent the population. The bias that results from an unrepresentative sample is called selection bias.
Ways of Selection Bias:Undercoverage A common type of sampling bias is to sample too few observations from a segment of the population. A commonly-cited example of undercoverage is the poll taken by the Literary Digest in 1936 that indicated that Landon would win an election against Roosevelt by a large margin when, in fact, Roosevelt won by a large margin. A common explanation is that poorer people were undercovered because they were less likely to have telephones and that this group was more likely to support Roosevelt.
Other Ways to Collect or useMisleading Statistic: We have already looked at selection bias. In groups of 5-6 Investigate all of the following ways to mislead consumers. Give examples to help your explanations 1) Use biased questions in your survey 2) Ask the wrong question 3) Use misleading graphs 4) Imply cause and effect when you only have correlation (what is correlation?) “Friends” causation http://www.youtube.com/watch?v=fzxO_51HK_c 5) Make your results more precise 6) Make up a statistic
Crime in AlburquerqueCan we trust statistics from th government?http://www.youtube.com/wa tch?v=MTbZoKEOkUg
Questions to Ask When Looking atData and Graphs Is the information presented correctly? Is the graph trying to influence you? Does the scale use a regular interval? What impression is the graph giving you?
What is Wrong with this Graph? You will be given five graphs to critically analyze in groups Discuss and decide as a group whether the graph is misleading . Give an explanation and reasons why or why not. If the graphs is misleading how could you improve this graph?
Year 7R is better at Maths than 7W. You will be given the year 7 Maths unit 1 test results In groups use this data to calculate mean, median and mode in a biased way to prove 7R is better at Maths than 7W! How would you do this? Use this data to manually draw (or use excel) a misleading graph that shows year 7R is better at Maths than 7W.