A Psychologist Has Performed the Following Experiment Can She Infer at the 5% Significance Level That There

question 43

Essay

A psychologist has performed the following experiment. For each of 10 sets of identical twins who were born 30 years ago, she recorded their annual incomes according to which twin was born first. The results (in $000) are shown below. $$\begin{array} { | c | c | c | } \hline \text { Twin set } & \text { First born } & \text { Second born } \\\hline 1 & 32 & 44 \\\hline 2 & 36 & 43 \\\hline 3 & 21 & 28 \\\hline 4 & 30 & 39 \\\hline 5 & 49 & 51 \\\hline 6 & 27 & 25 \\\hline 7 & 39 & 32 \\\hline 8 & 38 & 42 \\\hline 9 & 56 & 64 \\\hline 10 & 44 & 44 \\\hline\end{array}$$ Can she infer at the 5% significance level that there is a difference in income between the twins?

---

Definitions:

Problem-solving Ability

The capacity to find solutions for difficult or complex issues.

Literacy

The ability to read and write at a level adequate for communication or comprehension.

Economic Growth

The increase in the amount of goods and services produced by an economy over a period of time.

Declining Savings

A situation where the amount of money saved by individuals or entities decreases over time.