SWBAT: Distinguish between a parameter and a statistic and define a sampling distribution.
Do Now:
The variance of a random variable is 204.49. What is the standard deviation of that variable?
(A) 13.9
(B) 14.3
(C) 102.2
(D) 409.0
(E) 41,816.2
Claim: Mars and Co. reports that their M&M’s candies contain 20% orange.
1. Each of you have a bag of m&m’s. Open your bags and count out a random sample of 50
m&m’s. Disregard (or eat) the rest.
2. Out of your sample of 50, determine the proportion (𝑝̂ ) of orange m&m’s and record this
below:
𝑝̂ =
3. Let’s now, create a class dotplot to investigate the sampling variability of this claim:
4. Describe the shape, center, spread and any unusual values you see.
SWBAT: Distinguish between a parameter and a statistic and define a sampling distribution.
For our investigation:
a) Determine the parameter.
b) Determine the statistic.
c) Is our class dotplot the sampling distribution? Justify your answer.
SWBAT: Distinguish between a parameter and a statistic and define a sampling distribution.
Parameters and Statistics
A parameter is a number that describes some
characteristic of the population.
A statistic is a number that describes some characteristic
of a sample.
*Remember s and p: statistics come
from samples, and parameters come from populations.
Sampling Distribution
*The sampling distribution of a statistic is the distribution
of values taken by the statistic in all possible samples of
the same size from the same population.
*If the statistic of the sample is equal to the parameter of
the population then it is considered an unbiased estimator
of the parameter.
*You want the variability to be "low". Increase the sample
size to at least 10% of the population.
SWBAT: Distinguish between a parameter and a statistic and define a sampling distribution.
YOU TRY!!
Determine whether the underlined value is a parameter or
a statistic.
a. In a national survey on substance abuse, 10% of
respondents aged 12 to 17 reported using illicit drugs
within the past month.
b.Ty Cobb is one of major league baseball’s greatest
hitters of all time, with a career batting average of
0.366.
c. A study of 6076 adults in public rest rooms (in Atlanta,
Chicago, New York City, and San Francisco) found that
23% did not wash their hands before exiting.
d.Interview of 100 adults 18 years of age or older,
conducted nationwide, found that 44% could state the
minimum age required for the office of US president.