Sampling Error

n = ? M = 65 s = ?

Single Sample z test Problem 10.1

2 explanations of your data (using directional or non-directional language

depending on the research question)

tx

IV

population before tx

sample after tx

The independent variable is being manipulated with two treatments (hint: with an abstract problem like this, sometimes it helps to put in a real treatment, such as IV Pain Relievers with tx Ibuprofen and tx non-treatment)

H1: IV had an effect

H0: IV had no effect (all results are due to chance primarily through

sampling error)

Population µ = 60 σ = 10

High Prob. (easy)

Low Prob. (hard)

α = .05 Prob. calcul ation

single sample z test

Step 3: Using Part III of formula sheet, determine the

critical value(s)

half α

Reject H0 & Accept H1

(due to real effect)

Step 1: Diagram your study (noting the data you are given)

Step 2: Create a table of calculations for each of the terms which you will need to solve the

formulas (not needed in this problem)

high

Step 4: Calculate the z statistic

1. σm = σ 𝑛𝑛

2. z = 𝑀𝑀 −µ

σm

Step 5: Compare critical z to the calculated z & make a

decision about the H0 hypothesis

Step 6: Report results professionally (see last step of

formula sheet)

x x2

(data for sample) __ __ ∑= ∑=

∑(x)2=

2 outcomes 2 decisions

non-tx

high

Two tailed test: both tails

One tailed test: left or right tail

full α orand