Question

*Sampling with replacement*

- A researcher is interested in drawing a sample of potential voters from a population of 10 individuals. She settles on a sample size of 5, and sends out random invitations to 5 of the voters, by picking their names randomly from a list. How many possible samples could she draw from this population?

*Sampling without replacement*

- The researcher realizes that she made a mistake! She accidentally asked the selected some of the same voters more than once. She updates her sampling method to only sample each individual once. She again samples 5 voters. How many possible samples could she draw from this population?
- Let’s say we have the following data from a population:

7 |
10 |
15 |

a) What is the mean of this population?

b) If we were to sample with replacement, for a sample size of 2, how many samples could we get?

- Write out all the possible samples we could get, and calculate the mean for each of them. This is called the sampling distribution of the mean.

Sample |
Sample Mean ( |

- What is the mean of the Sample Means? (the mean of the sampling distribution)

*μ _{M}*= _____

- Using the following formula, calculate the variance of the sampling distribution from #4 (use the same sample and sample means here to fill in the table). This formula indicates how much each score deviates from the mean of the sampling distribution.

σ^{2}_{M=} (M-μ_{M})^{2} /
N^{n}

Sample |
Sample Mean ( |
( |
N^{2} |

Answer #1

Sample | Sample Mean |

7,7 | 7 |

7,10 | 8.5 |

7,15 | 11 |

10,7 | 8.5 |

10,10 | 10 |

10,15 | 12.5 |

15,7 | 11 |

15,10 | 12.5 |

15,15 | 15 |

Mean of the sampling mean is = = 96/9 = 10.67

1.
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Group of answer choices:
Standard error
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Standardization
Standard dispersion
----
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