1 / 12

Statistics and parameters

Statistics and parameters. To find out about a population we take a sample. Statistics describe features of the sample. What statistics do we use? How are they calculated?. We use sample statistics to make inferences about population parameters . Proportion Central tendency

traci
Download Presentation

Statistics and parameters

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Statistics and parameters

  2. To find out about a population we take a sample

  3. Statistics describe features of the sample What statistics do we use? How are they calculated?

  4. We use sample statistics to make inferences about population parameters Proportion Central tendency Variation or spread Shape Unusual features

  5. The Mean is easy to calculate and is also easily understood. BUT! It is affected by extreme values. The Measures of Central Tendency

  6. The Median is unaffected by extreme values, but it is more difficult to calculate as the data has to be ordered first. BUT! It is UNaffected by extreme values. The Measures of Central Tendency

  7. The Mode is useful to manufacturers who want to identify the most popular value. BUT! It is not always typical of a population as a whole. The Measures of Central Tendency

  8. The Mean is easy to calculate and is understood. BUT! It is affected by extreme values. The Measures of Central Tendency

  9. The Range is the difference between the maximum and minimum values. The range is easy to calculate and understand. BUT! If there are extreme values, the range does not accurately reflect how spread out the data values are. The Measures of Spread

  10. The Inter-quartile Range is the difference between the upper quartiles and the lower quartile and gives the range of the middle 50% of the data. As the extreme values are outside the middle 50% of the data, the inter-quartile range gives a clear indication of the spread. The Measures of Spread

  11. The Standard deviation is a calculated measure of spread which is shows how much variance there is from the mean. You can safely conclude that a set of data with a larger standard deviation is more spread out than a set of data with a smaller standard deviation. The Measures of Spread

More Related