stratified

  1. I

    Stratified Sampling

    A city has 90000 dwellings: 35000 are homes, 45000 are apartments, 10,000 are condos. i) You know the mean electricity use is roughly twice as much for homes as for apartments or condos, and the standard deviation is proportional to the mean so S_1 = 2S_2 = 2S_2. How would you distribute a...
  2. J

    Stratified vs. Cluster Sampling

    I think I'm getting the two confused. If I were to divide a university population by departments would this be stratified sampling, if each department is considered a strata? Or is it cluster sampling? Thanks
  3. A

    stratified sampling

    hi this is my question: A glass blower has made 8 wine glasses, 32 ornaments and 7 bottles in one day. he is going to check the quality of the items by looking at a 20% sample. A) Explain why he should use a straified sample rather than a random sample? i know using stratified sampling would...
  4. A

    stratified sampling

    hi, this is my question: a factory has 70 employees. A) Explain how you could obtain a random sample of 15 employees from this factory? would this be alright to do: 35/70 X 15= 7.5 = 8 people 35/70 X 15= 7.5 = 8 people 8+8 =16 so then i would -1 away from one of them so it makes 15?
  5. N

    Stratified Sampling

    Here is the question: When using stratified sampling, does everyone in the population have an equal chance of being selected? My initial thought is that generally everyone does have an equal chance of being selected. But that is only true if everyone has the chance of being selected. By which I...