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

question 39

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?

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Definitions:

Unadjusted Year End

The fiscal year-end date prior to any adjustments made for accounting purposes.

Trial Balance

A bookkeeping worksheet in which the balances of all ledgers are compiled into debit and credit account column totals that are equal, used to ensure the accounting system's mathematical accuracy.

Allowance for Uncollectibles

An estimation of the accounts receivable that a company does not expect to collect, used to adjust financial statements.

Gross Receivables

The aggregate financial obligation customers have to a company, prior to any reductions for potential uncollectible debts.