Lauren is conducting a study on the decision making processes an individual goes through when buying items. Specifically, Lauren is measuring the attributes and mental connections made when making a purchase. Lauren is collecting measures for her dependent variable.

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.

Emery pharmaceutical uses an unstable chemical compound that must be kept in an environment where both temperature and humidity can be controlled. emery uses 825 pounds per month of the chemical, estimates the holding cost to be 50% of the purchase price (because of spoilage), and estimates order costs to be $48 per order. the cost schedules of two suppliers are as follows: vendor 1 vendor 2 quantity price/lb quantity price/lb 1-499 $17 1-399 $17.10 500-999 $16.75 400-799 $16.85 1000+ $16.50 800-1199 $16.60 1200+ $16.25 (a) what is the economic order quantity for each supplier? (b) what quantity should be ordered and which supplier should be used? (c) the total cost for the most economic order sire is $

When a company produces and sells x thousand units per week, its total weekly profit is p thousand dollars, where upper p equals startfraction 800 x over 100 plus x squared endfraction . the production level at t weeks from the present is x equals 4 plus 2 t. find the marginal profit, startfraction dp over dx endfraction and the time rate of change of profit, startfraction dp over dt endfraction . how fast (with respect of time) are profits changing when tequals8?