Class 4 formulas of educational statistics

Formulas of statistics

1. UNIVERSIDAD DE GUAYAQUIL
FACULTAD DE FILOSOFÍA LETRAS Y CIENCIAS DE LA
EDUCACIÓN
STATISTICS II
INTRODUCTION TO EDUCATIONAL STATISTICS
Facilitator:
MALO TOLEDO CLAUDIO

2. n= Sample we want to find
z= confidence level
p= probability in favor or success (standard deviation)
q= Probability against or failure
N= population
e = margin of error (0.05) 95%
Note: When there are not surveys backgrounds p and q will
always be 50% (0.50)

3. Confidencelevel:A confidence level is an expression of how confident a
researcher can be of the data obtained from a sample. Confidence levels are
expressed as a percentage and indicate how frequently that percentage of the
target population would give an answer that lies within the confidence interval.
80, 85, 90, 95, 97, 99%
Margin of error: Margin of error estimates how far real population values may
fall from your sample responses. For example, if you run a survey with margin of
error of 5%, and 45% of respondents said that they're interested in learning
more about your product, you should interpret it as: "40% to 50% of the
population was interested in learning more". As you can see, margin of error
works both ways: +5% or -5% of the sample average, forming what is commonly
called "Confidence Interval". You don't know for sure where within that
interval the actual interest level lies for the entire population because if you
rerun the survey, answers will fluctuate somewhat every time. 0.05

4. How to obtain the sample from the population

5. How to obtain the sample from the population

7. Example: Which would be the size of the simple of a population
of 350 people, where we are going to work with a level of
confidence of the 95% and a margin of error of 5%. Lets
remember that if there is no previous surveys or information p
and q would be 50%