Technique Lab 1- Activity Bases statistics

Question 1

what were the main methods of part A

Answer 1

A
- Sort 250 pennies by year. See what the distribution is by laying out pennies in a histogram
- Calculate mean, variance, and standard deviation of age distribution of pennies
B
- Then do random sampling of sizes 5, 10, and 25 with replacement after a full trial. record date
- Find mean age and mean and standard deviation of the sample of the 5 average draw values
C
- Set of random 250 pennies. Selects random ste of 10 pennies and with replacement. Generate 100 sets of 10 random ages
- Find mean age for each of the 100 sets. Create 4 histograms:
- A histogram is a graph commonly used to sow frequency distributions

Question 2

what were the main methods of part 2

Answer 2

• Launching gummy bears from a catapult
• 2 independent variable: fulcrum placement (A or B) and placement of the gummy bear launch slot (1,2,3)
• Dependent variable: the distance travelled by the gummy bear after launch
• Randomly decide the gummy bear being used to launch, randomly decide the placement of the catapult (6 possible conditions, A1, A2, A3, B1, etc), and randomly decide who is launching. 4 trials in in condition
• Find mean of distance travelled for the 4 gummy bears in each trial. Make scatter with smooth lines and markers. Separate graph for each independent variable
• Found that there was interaction. One independent variables affect on the dependant variable is influenced by the other independent variable.

Question 3

what is the central limit therem

Answer 3

• If you have a population with mean μ and standard deviation σ and take sufficiently large random samples from the population WITH REPLACEMENT, then the distribution of the sample means will be approximately normally distributed
• Holds true for normal or skewed source population, provided n>= 30. Holds true for normal with smaller than 30

Question 4

what is factorial design

Answer 4

• Each level of one independent variable is combined with each level of the other to produce ALL possible combinations. Combinations= conditions
• 2x2 factorial design is two independent variable on one dependant
• Can show you MAIN EFFECTS: effects of just one independent variable has on the
  dependent variable
• Also shows INTERACTION EFFECTS: the effect of one independent variable has on the dependent variable DEPENDS on the level of the OTHER independent variable
• Parallel= NO interaction non parallel: INTERACTION

Question 5

standard deviation

Answer 5

standard deviation of pop over root smaple size