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Bias is a non-sampling error (error occurring during the process of gathering data) that is systematic and deprives a statistical result of its representativeness. It is cumulative as the sample size increases rather than balancing out like random errors.
Ways that bias is introduced include:
-Deliberate selection based on personal judgment of what is representative
- Having substitute members or units that are convenient rather than because of difficulty in making contact with given units.
- Failure to cover the whole of the selected sample like when some people do not answer questioners
- Haphazard selection by human beings rather than being random
- Inadequate, hasty, incomplete and misleading interviewing.
Sampling bias is tolerated in some investigations. Unbiased sample is one that is free from selection and
procedural bias
Wilfykil answered the question on February 20, 2019 at 11:42
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Date posted: February 20, 2019. Answers (1)
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Required:
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Date posted: February 20, 2019. Answers (1)
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Required:
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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Required:
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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A fruit/juice kiosk along Lusaka road, VegFresh kiosk has come up with the following formulae of making natural juice for its industrial area customers
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The selling prices of the fruit juices per every 5 litre are:
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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Date posted: February 20, 2019. Answers (1)
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iii) Chain base method.
iv) Weighted index number.
v) Quantity index number.(Solved)
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Date posted: February 20, 2019. Answers (1)
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In brand switching between different toothpastes named Closed-up CU, Cols-gate CG and Aquas-fresh AF, the state transition matrix below is obtained for a particular month.
Required:
i) If the market share for the different toothpastes were 0.4, 0.3 and 0.3 for CU, CG and AF for January 2002, what will be the market share in February 2002 and March 2002?
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Date posted: February 20, 2019. Answers (1)