Gross private domestic investment $1,593 personal taxes 1,113 transfer payments 1,683 taxes on production and imports 695 corporate income taxes 213 personal consumption expenditures 7,304 consumption of fixed capital 1,393 us exports 1,059 dividends 434 government purchases 1,973 net foreign factor income 10 undistributed corporate profits 141 social security contributions 748 us imports 1,483 statistical discrepancy 50 refer to the accompanying national income data (in billions of dollars). net private domestic investment is equal to

Reliability and validity reliability and validity are two important considerations that must be made with any type of data collection. reliability refers to the ability to consistently produce a given result. in the context of psychological research, this would mean that any instruments or tools used to collect data do so in consistent, reproducible ways. unfortunately, being consistent in measurement does not necessarily mean that you have measured something correctly. to illustrate this concept, consider a kitchen scale that would be used to measure the weight of cereal that you eat in the morning. if the scale is not properly calibrated, it may consistently under- or overestimate the amount of cereal that’s being measured. while the scale is highly reliable in producing consistent results (e.g., the same amount of cereal poured onto the scale produces the same reading each time), those results are incorrect. this is where validity comes into play. validity refers to the extent to which a given instrument or tool accurately measures what it’s supposed to measure. while any valid measure is by necessity reliable, the reverse is not necessarily true. researchers strive to use instruments that are both highly reliable and valid.