Hypothesis Questions

Turn-in Assignment for Unit #1

1.      For each of the scenarios below, specify the branch of statistics (D for descriptive or I for inferential) being illustrated:

(a) a college employee prepared a frequency distribution of the ages of the college's 11,000 students        _____

(b) based on a survey of 1000 consumers, it was determined with 99% confidence that between 80 and 85 per cent of all U.S. consumers reduced
their beef consumption last quarter  _____

(c) in a particular county, the median household income of those households surveyed by the Census Bureau in 2007 was $34,000  _____

(d) an analysis of the weights of a sample of 10 crates of oranges in a large shipment received from a supplier caused a grocery store manager to conclude the mean weight of all the crates in the shipment was below the required minimum  _____

2.      Identify each of the following with the appropriate symbol:   

a)  size of sample;                                      ______

b)  mean of sample;                                   ______

c)  standard deviation of sample;              ______

      d) mean of population;                              ______

      e)  standard deviation of population         ______

3.  Below are the fiber contents (in grams) of eight‑ounce servings for a sample of cereals sold in a  grocery store:

                            0, 1, 4, 2, 0, 1, 0, 0, 1

Determine for this sample:

(a) the mean fiber content  _____

(b) the median fiber content _____

(c) the mode fiber content _____

(d) the variance in the fiber content _____

(e) the third quartile _____

7.  For each of the following variables, identify whether it is qualitative – “L” or quantitative – “N” and indicate its scale of measurement (Nominal –“N”, Ordinal – “O”, Ratio – “R”, Interval – “I”, :

(a) weight of a truck weighed in at a particular weighing station yesterday  _____   _____

(b) number of employees in a small business  _____   _____

(c) favorite TV program of a senior citizen in the U.S.  _____   _____

(d) completed level of education (less than high school, high school, bachelor’s degree, advanced degree) of an adult in Georgia  _____   _____

(e) noonday temperature (in degrees Celsius) in Kennesaw  _____   _____

9. At the right is the (hypothetical)                             x          f(x)

    probability distribution of                                       0          .20

    X = "the number of PCs (personal                          1          .58

    computers) in a randomly selected                         2          .18

    residence in Mississippi"                                         3          .04

(a)    What is the probability that a randomly selected residence in Mississippi contains at least two PCs?   _____

(b) What is the mean number of PCs in the residences in Mississippi?  _____

(c) What is the standard deviation in the number of PCs in the residences?  _____