Anatomy homework help. Formula sheet(Unit 3(
- Sampling distribution of mean: = N(m, s/);
Mean = m, new standard deviation for sample mean = s/
is also called standard error for sample mean
To calculate percent or probability, use
Normalcdf(lower, upper, m, s/)
- Sampling distribution of proportion: z = ,
Mean proportion=p
Standard deviation of proportion =
Confidence interval for proportion : Stat, Tests, 1PropZInt
3. Margin of error = E =
Confidence = Middle area, = Invnorm(Left area, 0, 1)
- Sample size n(How many?)
n =……..Take the next larger number.
- One sample proportion z test: Stat, tests, 1-PropZTest
- Student t-distribution for mean:
- Confidence interval for mean : TInterval
- Test of hypotheses for mean : TTest
- Comparing two groups:
- Comparing two proportions:
(i) Confidence interval: 2PropZInt
(ii)Test of hypotheses : 2PropZTest
b. Comparing two means:
(i) Confidence interval : 2SampTInt
(ii)Test of hypotheses: 2SampTTest
Paired data: =
Confidence interval: TInterval
Test of hypotheses: TTest
- Chi Square test:
- Goodness if fit test : df = n-1
Stat, tests, GOF-Test ——– for column data with frequency
- Independence test
degree of freedom = df = (r-1)(c-1); [‘r’ means row and ‘c’ means
column]
2^{nd} Matrix, edit. m x n
Stat, Tests, Test ——— for contingency table
Expected matrix: 2nd Matrix edit [B]
You need to calculate expected matrix after you finish the test.
c. Homogeneity test: Same process as independence test
except the hypotheses ( ‘same’ or ‘different’
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Conditions / assumptions:
A). For proportion(z distribution)
Sample values are independent, randomized,
sample size is less than 10% of the population size,
np 10, nq 10 (Check this one)
B). For mean(t distribution)
Sample values are independent, randomized
Sample size is less than 10% of the population size
Distribution is nearly normal.
C). For test:
The sampling method is simple random sampling.
The variable under study is categorical.
Observed values are counts
Expected values are at least 5.
Notes: If (sigbnificance) is not given, choose it to be 5% (.05)
If Confidence is not given, choose it to be 95%
If proportion is not given , choose it to be 0.5 (50%)
P-value < , reject H0
P-value > , do not reject H0
Larger n, smaller error. Smaller n, larger error
Larger confidence, larger error. Smaller confidence, smaller error