Do all the exercises by writing (unless otherwise specified).

Transcription

1 EXERCISES: Do all the exercises by writing (unless otherwise specified). If an exercise asks you to state something, write it precisely and concisely with one sentence (unless otherwise specified, of course). If an exercise asks you to give something, write it out but it does not have to be one sentence. It could be a line or words. If an exercise asks you to find something, it is generally a computational exercise. State what you need to make correct decisions. State what could lead to incorrect decision. State where you find necessary information in Statistics. State what biased data are. Give two processes in which biased data can occur. Give what is used to take measurements in Statistics. State what a biased sampling process is. State what an unbiased sampling process is. State two things that can bias the data in Political Poll Example. State what a random number table is. State the reason why the average of all digits in a random number table should be close to

2 If you form three-digit numbers from the digits in a random number table (do not use a digit more than once), then what should the average of all these three-digit numbers be close to? If one of measuring and sampling processes is biased, the data are also biased. True or false? If both measuring and sampling processes are biased, then data are unbiased. True or false? State what multi-stage sampling is. State when a multi-stage sampling should be used. State what measuring process is. Give two things that result in biased data in a measuring process discussed in this section. State what sampling process is. Which process comes before the other (if both processes take place), a measuring process or a sampling process? State what a biased sample is. State what a biased sampling process is. State what an unbiased sampling process is. Give two samplings that could results in biased data. Give a sampling that results in an unbiased sample. Is raffle ticket sampling biased or unbiased sampling? State what stratified sampling is. State what a stratum is. 2

3 Multi-stage sampling is an unbiased sampling. True or false? Multi-stage sampling is a random sampling. True or false? Stratified sampling is an unbiased sampling? True or false? Stratified sampling is a random sampling? True of false? Simple random sampling is an unbiased sampling. True or false? Simple random sampling is a random sampling. True or false? State the example of convenience sampling, given in this section. State an example of convenience sampling, not given in this section. State the example of systematic sampling, given in this section. State an example of systematic sampling, not given in this section. State what random sampling is. State when a stratified sampling is used. State when a multi-stage sampling should be used. State what a random number generator does. Is random sampling unbiased sampling or biased sampling? Give two things used in random sampling when raffle ticket sampling is not possible. State what a sampling frame is. If you generate digits from a random number generator, how many each digit do you expect among the generated digits? Is stratified sampling an unbiased sampling (of course, provided done correctly)? 3

4 Is multi-stage sampling an unbiased sampling (of course, provided done correctly)? State the reason why your answer to the last question is correct. If a sampling frame contains objects, how many digits from a random number generator do you use for a number. If you make a number using five digits in a random number table (use each every digit in the table only once) and compute the average of all these numbers, what number should the average of these numbers be close to? State what a seed for a random number generator does. State what results from different seeds for a random number generator. Do the following exercises based on Campus Opinion Survey Example. Give the sample size. Give the population. Give the population size. State what a sampling frame is. State the purposes of this example. State the example. Give the name of sampling conducted in this example. How many strata in sampling? What property of objects is used for stratifying? Do the following exercises based on Business Audit Example. 4

5 Give the sample size. Give the population. Give the population size. State what a sampling frame is. State the reason why three digits from a random number generator are used for a number. State the reason why 150 digits are generated. State the purposes of this example. State the example. Give the name of sampling conducted in this example. Do the following exercise based on Households Sampling Example. Give the sample size. Give the population. Give the population size. State what sampling frames are. State the purposes of this example. State the example. Give the name of sampling conducted in this example. How many stages in the sampling? 5

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