Question

A researcher wants to study the effects of using the brain training software Lumosity on working memory. The researcher thinks that it may actually help working memory, or it could be a drain on limited cogntive resources and hurt working memory. She randomly samples 50 individuals tests their working memory capacity after using Lumosity for 2 months. Working memory scores in the population are known to be normally distributed with a mean of 4 items, and a standard deviation of 1 item.

Population 1:

Population 2:

Research Hypothesis:

Null Hypothesis:

Answer 1

From given scenario, we have the following information about given hypothesis testing.

Population 1: Working memories of all individuals before using the brain training software Lumosity

Population 2: Working memories of all individuals after using the brain training software Lumosity

Research (Alternative) Hypothesis (Claim): H_a:There is a significant effect of the brain training software Lumosity on the working memory.

Null Hypothesis: H₀: There is no any significant effect of the brain training software Lumosity on the working memory.

H₀: µ₁ = µ₂ versus H_a: µ₁ ≠ µ₂

This is a two tailed test.