A researcher is interested in the effect on test scores of computer usage. using school district​ data, she regresses district average test scores on the number of computers per student. what are po

A researcher is interested in the effect on test scores of computer usage. using school district​ data, she regresses district average test scores on the number of computers per student. what are possible sources of bias for modifyingabove beta 1 with caretβ1​, the estimated effect on tests scores of increasing the number of computers per​ student? for each source of bias​ below, determine whether modifyingabove beta 1 with caretβ1 will be biased up or down. 1. average income per capita in the district. if this variable is​ omitted, it will likely produce​ a(an) ▼ upward downward bias of the estimated effect on tests scores of increasing the number of computers per student. 2. the availability of computerized adaptive learning tools in the district. if this variable is​ omitted, it will likely produce​ a(an) ▼ upward downward bias of the estimated effect on tests scores of increasing the number of computers per student. 3. the availability of​ computer-related leisure activities in the district. if this variable is​ omitted, it will likely produce​ a(an) ▼ upward downward bias of the estimated effect on tests scores of increasing the number of computers per student.